##### Table of Contents





UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549





FORM 10-Q





(Mark One)

|x | QUARTERLY REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ---------------------------------------------------------------------------------

For the quarterly period ended March 31, 2010.



| ̈ | TRANSITION REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ----------------------------------------------------------------------------------

Commission file number 000-21898





ARROWHEAD
RESEARCH CORPORATION

(Exact name of registrant as specified in its charter)







|                         |  |                                     
|------------------------ |  | ------------------------------------
|Delaware                 |  | 46-0408024                          
|(State of incorporation) |  | (I.R.S. Employer Identification No.)

201 S. Lake Avenue, Suite 703

Pasadena, California 91101

(626) 304-3400

(Address and telephone number of principal executive offices)





Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Exchange Act during
the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90
days.    Yes  x    No   ̈

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File
required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such
files).    Yes   ̈    No   ̈

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer a non-accelerated filer, or a smaller reporting company.
See the definitions of large accelerated filer, accelerated filer and smaller reporting company in Rule 12b-2 of the Exchange Act. (Checked one):



|                                                                        |  |                              |  |  |  | 
|----------------------------------------------------------------------- |  | ---------------------------- |  |  |  | 
|Large accelerated   ̈                                                    |  | Accelerated filer   ̈        
|Non-accelerated filer   ̈  (Do not check if a smaller reporting company) |  | Smaller reporting company  x

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange
Act).    Yes   ̈    No  x

The number of shares outstanding of the issuers classes of common equity, as of the latest practicable date is 63,913,753 shares of Common Stock as
of May 7, 2010.









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##### Table of Contents

|                                                                                                                                                               |  |        
|-------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | -------
|                                                                                                                                                               |  | Page(s)
|                                                                                                                                                               | 
|PART IFINANCIAL INFORMATION                                                                                                                                   |  |        
|                                                                                                                                                               | 
|ITEM 1. FINANCIAL STATEMENTS                                                                                                                                   |  |        
|                                                                                                                                                               | 
|Consolidated Balance Sheets as of March 31, 2010 (unaudited) and September 30,
2009                                                                            |  | 1      
|                                                                                                                                                               | 
|Consolidated Statements of Operations for the three months and six months ended March 
31, 2010 and 2009 and from inception through March 31, 2010 (unaudited) |  | 2      
|                                                                                                                                                               | 
|Consolidated Statement of Stockholders Equity for the period from inception through March 
31, 2010 (unaudited)                                               |  | 3      
|                                                                                                                                                               | 
|Consolidated Statements of Cash Flows for the three and six months ended March 
31, 2010 and 2009 and from inception through March 31, 2010 (unaudited)        |  | 4      
|                                                                                                                                                               | 
|Notes to Consolidated Financial Statements (unaudited)                                                                                                         |  | 6      
|                                                                                                                                                               | 
|ITEM 2. MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS                                                                  |  | 16     
|                                                                                                                                                               | 
|ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK                                                                                             |  | 26     
|                                                                                                                                                               | 
|ITEM 4T. CONTROLS AND PROCEDURES                                                                                                                               |  | 26     
|                                                                                                                                                               | 
|PART IIOTHER INFORMATION                                                                                                                                      |  |        
|                                                                                                                                                               | 
|ITEM 1. LEGAL PROCEEDINGS                                                                                                                                      |  | 27     
|                                                                                                                                                               | 
|ITEM 1A. RISK FACTORS                                                                                                                                          |  | 27     
|                                                                                                                                                               | 
|ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS                                                                                            |  | 36     
|                                                                                                                                                               | 
|ITEM 3. DEFAULTS UPON SENIOR SECURITIES                                                                                                                        |  | 36     
|                                                                                                                                                               | 
|ITEM 4. (REMOVED AND RESERVED)                                                                                                                                 |  | 36     
|                                                                                                                                                               | 
|ITEM 5. OTHER INFORMATION                                                                                                                                      |  | 36     
|                                                                                                                                                               | 
|ITEM 6. EXHIBITS                                                                                                                                               |  | 37     
|                                                                                                                                                               | 
|SIGNATURES                                                                                                                                                     |  | 38     



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##### Table of Contents

PART I. FINANCIAL INFORMATION



|ITEM 1. | FINANCIAL STATEMENTS
|------- | --------------------

Arrowhead Research Corporation and Subsidiaries

(A Development Stage Company)

Consolidated Balance Sheets



|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | ------------------------- | ------------ | - | ----------------- | - | ------------ | -
|                                                                                                                                                                                 |  | (unaudited)March 31, 2010 |              |   | September 30,2009 |  
|ASSETS                                                                                                                                                                           |  |                           |              |   |                   |   |              |  
|CURRENT ASSETS                                                                                                                                                                   |  |                           |              |   |                   |   |              |  
|Cash and cash equivalents                                                                                                                                                        |  | $                         | 2,593,044    |   |                   | $ | 2,020,224    |  
|Trade receivable, net of allowance for doubtful accounts of $90,789 at March 31, 2010 and $30,789 at September 30, 2009                                                          |  |                           | 55,937       |   |                   |   | 144,148      |  
|Other receivables                                                                                                                                                                |  |                           | 116,382      |   |                   |   | 3,109        |  
|Prepaid expenses                                                                                                                                                                 |  |                           | 225,107      |   |                   |   | 316,074      |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|TOTAL CURRENT ASSETS                                                                                                                                                             |  |                           | 2,990,470    |   |                   |   | 2,483,555    |  
|PROPERTY AND EQUIPMENT                                                                                                                                                           |  |                           |              |   |                   |   |              |  
|Computers, office equipment and furniture                                                                                                                                        |  |                           | 374,991      |   |                   |   | 374,991      |  
|Research equipment                                                                                                                                                               |  |                           | 932,683      |   |                   |   | 932,683      |  
|Software                                                                                                                                                                         |  |                           | 150,445      |   |                   |   | 150,445      |  
|Leasehold improvements                                                                                                                                                           |  |                           | 94,317       |   |                   |   | 94,317       |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|                                                                                                                                                                                 |  |                           | 1,552,436    |   |                   |   | 1,552,436    |  
|Less: Accumulated depreciation and amortization                                                                                                                                  |  |                           | (1,214,306   | ) |                   |   | (1,025,392   | )
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|NET PROPERTY AND EQUIPMENT                                                                                                                                                       |  |                           | 338,130      |   |                   |   | 527,044      |  
|OTHER ASSETS                                                                                                                                                                     |  |                           |              |   |                   |   |              |  
|Rent deposit                                                                                                                                                                     |  |                           | 104,725      |   |                   |   | 109,648      |  
|Patents                                                                                                                                                                          |  |                           | 2,204,648    |   |                   |   | 2,362,460    |  
|Investment in Nanotope Inc., equity basis                                                                                                                                        |  |                           | 1,933,230    |   |                   |   | 2,032,467    |  
|Investment in Leonardo Biosystems Inc., at cost                                                                                                                                  |  |                           | 187,000      |   |                   |   | 187,000      |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|TOTAL OTHER ASSETS                                                                                                                                                               |  |                           | 4,429,603    |   |                   |   | 4,691,575    |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|TOTAL ASSETS                                                                                                                                                                     |  | $                         | 7,758,203    |   |                   | $ | 7,702,174    |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|LIABILITIES AND STOCKHOLDERS EQUITY                                                                                                                                             |  |                           |              |   |                   |   |              |  
|CURRENT LIABILITIES                                                                                                                                                              |  |                           |              |   |                   |   |              |  
|Accounts payable                                                                                                                                                                 |  | $                         | 884,018      |   |                   | $ | 1,013,281    |  
|Accrued expenses                                                                                                                                                                 |  |                           | 407,161      |   |                   |   | 420,077      |  
|Accrued payroll and benefits                                                                                                                                                     |  |                           | 168,536      |   |                   |   | 160,846      |  
|Accrued severance                                                                                                                                                                |  |                           | 23,500       |   |                   |   | 23,500       |  
|Capital lease obligation                                                                                                                                                         |  |                           | 296,419      |   |                   |   | 726,534      |  
|Note payable                                                                                                                                                                     |  |                           | 500,000      |   |                   |   |             |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|TOTAL CURRENT LIABILITIES                                                                                                                                                        |  |                           | 2,279,634    |   |                   |   | 2,344,238    |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|LONG-TERM LIABILITIES                                                                                                                                                            |  |                           |              |   |                   |   |              |  
|Note payable                                                                                                                                                                     |  |                           |             |   |                   |   | 500,000      |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|TOTAL LONG-TERM LIABILITIES                                                                                                                                                      |  |                           |             |   |                   |   | 500,000      |  
|Commitments and contingencies                                                                                                                                                    |  |                           |              |   |                   |   |              |  
|STOCKHOLDERS EQUITY                                                                                                                                                             |  |                           |              |   |                   |   |              |  
|Arrowhead Research Corporation shareholders equity:                                                                                                                             |  |                           |              |   |                   |   |              |  
|Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued or outstanding                                                                                  |  |                           |             |   |                   |   |             |  
|Common stock, $0.001 par value; 145,000,000 shares authorized; 63,913,753 and 56,411,774 shares issued and outstanding as of
March 31, 2010 and September 30, 2009, respectively |  |                           | 63,929       |   |                   |   | 56,428       |  
|Additional paid-in capital                                                                                                                                                       |  |                           | 114,181,556  |   |                   |   | 110,070,327  |  
|Subscription receivable                                                                                                                                                          |  |                           |             |   |                   |   | (300,000     | )
|Accumulated deficit during the development stage                                                                                                                                 |  |                           | (108,367,706 | ) |                   |   | (104,968,819 | )
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|Total Arrowhead Research Corporation stockholders equity                                                                                                                        |  |                           | 5,877,779    |   |                   |   | 4,857,936    |  
|Noncontrolling interest                                                                                                                                                          |  |                           | (399,210     | ) |                   |   |             |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|TOTAL STOCKHOLDERS EQUITY                                                                                                                                                       |  |                           | 5,478,569    |   |                   |   | 4,857,936    |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  
|TOTAL LIABILITIES AND STOCKHOLDERS EQUITY                                                                                                                                       |  | $                         | 7,758,203    |   |                   | $ | 7,702,174    |  
|                                                                                                                                                                                 |  |                           |              |   |                   |   |              |  

The accompanying notes are an integral part of these consolidated financial statements.



1



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##### Table of Contents

Arrowhead Research Corporation and Subsidiaries

(A Development Stage Company)

Consolidated Statements of Operations

(unaudited)



|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|---------------------------------------------------------------------------------------- |  | --------------------------- | ---------- | - | --------------------------- | - | ---------- | ------------------------- |  | - | ------------------------- | - |  | -------------------------------------- | ----------- | - |  | - | ------------ | -
|                                                                                         |  | Three Months Ended3/31/2010 |            |   | Three Months Ended3/31/2009 |   |            | Six Months Ended3/31/2010 |  |   | Six Months Ended3/31/2009 |   |  | May 7, 2003(Inception) toMarch 31,2010 |            
|REVENUE                                                                                  |  | $                           | 157,346    |   |                             | $ | 235,650    |                           |  | $ | 305,414                   |   |  | $                                      | 937,373     |   |  | $ | 7,813,053    |  
|OPERATING EXPENSES                                                                       |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Salaries                                                                                 |  |                             | 1,045,121  |   |                             |   | 2,434,489  |                           |  |   | 2,149,224                 |   |  |                                        | 5,561,154   |   |  |   | 42,183,762   |  
|Consulting                                                                               |  |                             | 78,020     |   |                             |   | 343,994    |                           |  |   | 179,259                   |   |  |                                        | 932,750     |   |  |   | 8,011,416    |  
|General and administrative expenses                                                      |  |                             | 733,713    |   |                             |   | 1,026,353  |                           |  |   | 1,479,963                 |   |  |                                        | 2,611,105   |   |  |   | 24,544,790   |  
|Research and development                                                                 |  |                             | 351,045    |   |                             |   | 1,506,548  |                           |  |   | 628,833                   |   |  |                                        | 5,394,853   |   |  |   | 54,248,991   |  
|Patent amortization                                                                      |  |                             | 78,906     |   |                             |   | 118,556    |                           |  |   | 157,812                   |   |  |                                        | 208,086     |   |  |   | 1,944,278    |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|TOTAL OPERATING EXPENSES                                                                 |  |                             | 2,286,805  |   |                             |   | 5,429,940  |                           |  |   | 4,595,091                 |   |  |                                        | 14,707,948  |   |  |   | 130,933,237  |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|OPERATING LOSS                                                                           |  |                             | (2,129,459 | ) |                             |   | (5,194,290 | )                         |  |   | (4,289,677                | ) |  |                                        | (13,770,575 | ) |  |   | (123,120,184 | )
|OTHER INCOME (EXPENSE)                                                                   |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Loss on equity of investmentsNanotope                                                   |  |                             | (50,599    | ) |                             |   | (60,032    | )                         |  |   | (99,238                   | ) |  |                                        | (129,412    | ) |  |   | (439,771     | )
|Gain on sale of stock in subsidiary                                                      |  |                             |           |   |                             |   |           |                           |  |   |                          |   |  |                                        |            |   |  |   | 2,292,800    |  
|Gain on sale of equity of investmentsEnsysce                                            |  |                             |           |   |                             |   |           |                           |  |   |                          |   |  |                                        | 700,000     |   |  |   | 700,000      |  
|Gain/(loss) on sale of fixed assets, net                                                 |  |                             | 50,000     |   |                             |   | 52,457     |                           |  |   | 50,000                    |   |  |                                        | 52,457      |   |  |   | (27,374      | )
|Realized and unrealized gain in marketable securities                                    |  |                             |           |   |                             |   |           |                           |  |   |                          |   |  |                                        |            |   |  |   | 382,264      |  
|Interest income (expense), net                                                           |  |                             | (14,777    | ) |                             |   | (65,382    | )                         |  |   | (36,802                   | ) |  |                                        | (56,513     | ) |  |   | 2,773,153    |  
|Other income                                                                             |  |                             | 1,675      |   |                             |   |           |                           |  |   | 1,895                     |   |  |                                        |            |   |  |   | 179,785      |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|TOTAL OTHER INCOME (EXPENSE)                                                             |  |                             | (13,701    | ) |                             |   | (72,957    | )                         |  |   | (84,145                   | ) |  |                                        | 566,532     |   |  |   | 5,860,857    |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|LOSS FROM CONTINUING OPERATIONS                                                          |  |                             | (2,143,160 | ) |                             |   | (5,267,247 | )                         |  |   | (4,373,822                | ) |  |                                        | (13,204,043 | ) |  |   | (117,259,327 | )
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Gain/(loss) from discontinued operations                                                 |  |                             | 563        |   |                             |   | (22,032    | )                         |  |   | (15,204                   | ) |  |                                        | (115,764    | ) |  |   | (7,581,671   | )
|Gain/(loss) on disposal of discontinued operations                                       |  |                             |           |   |                             |   |           |                           |  |   | 430,000                   |   |  |                                        |            |   |  |   | 789,375      |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|INCOME (LOSS) FROM DISCONTINUED OPERATIONS                                               |  |                             | 563        |   |                             |   | (22,032    | )                         |  |   | 414,796                   |   |  |                                        | (115,764    | ) |  |   | (6,792,296   | )
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Provision for income taxes                                                               |  |                             |           |   |                             |   |           |                           |  |   |                          |   |  |                                        |            |   |  |   |             |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|NET LOSS                                                                                 |  |                             | (2,142,597 | ) |                             |   | (5,289,279 | )                         |  |   | (3,959,026                | ) |  |                                        | (13,319,807 | ) |  |   | (124,051,623 | )
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Less: Net loss attributable to noncontrolling interests                                  |  |                             | 288,637    |   |                             |   |           |                           |  |   | 560,139                   |   |  |                                        | 60          |   |  |   | 15,847,877   |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|NET LOSS ATTRIBUTABLE TO ARROWHEAD                                                       |  | $                           | (1,853,960 | ) |                             | $ | (5,289,279 | )                         |  | $ | (3,398,887                | ) |  | $                                      | (13,319,747 | ) |  | $ | (108,203,746 | )
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Earnings per sharebasic and diluted:                                                    |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Income (loss) from continuing operations attributable to Arrowhead common shareholders   |  | $                           | (0.03      | ) |                             | $ | (0.12      | )                         |  | $ | (0.07                     | ) |  | $                                      | (0.31       | ) |  |   |              |  
|Income (loss) from discontinued operations attributable to Arrowhead common shareholders |  |                             |           |   |                             |   |           |                           |  |   | 0.01                      |   |  |                                        |            |   |  |   |              |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Net income (loss) attributable to Arrowhead shareholders                                 |  | $                           | (0.03      | ) |                             | $ | (0.12      | )                         |  | $ | (0.06                     | ) |  | $                                      | (0.31       | ) |  |   |              |  
|                                                                                         |  |                             |            |   |                             |   |            |                           |  |   |                           |   |  |                                        |             |   |  |   |              |  
|Weighted average shares outstandingbasic and diluted                                    |  |                             | 62,922,539 |   |                             |   | 42,934,517 |                           |  |   | 60,774,007                |   |  |                                        | 42,934,517  |   |  |   |              |  

The accompanying notes are an integral part of these consolidated financial statements.



2



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##### Table of Contents

Arrowhead Research Corporation and Subsidiaries

(A Development Stage Company)

Consolidated Statement of Stockholders Equity

from inception through March 31, 2010

(Unaudited)



|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|------------------------------------------------------------------------------------------- |  | ------------ |  | ------------------------- | ------ |  | ---------------------- | ----------- | - | -------------------------------------------- | - | -------- | ---------------------- |  | - | ------------ | - |  | - | --------- | - |  | - | ----------- | -
|                                                                                            |  | Common Stock |  | AdditionalPaid-in-Capital |        |  | SubscriptionReceivable |             |   | AccumulatedDeficitduring theDevelopmentStage |   |          | Noncontrollinginterest |  |   | Totals       |  
|                                                                                            |  | Shares       |  | Amount                    |        |  |                        |             |  
|Initial Issuance of Stock:                                                                  |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Common stock & warrants issued for cash @ $0.001 per unit                                   |  | 3,000,000    |  | $                         | 3,000  |  | $                      |            |   |                                              | $ |         |                        |  | $ |             |   |  | $ |          |   |  | $ | 3,000       |  
|Common stock & warrants issued for cash @ $1.00 per unit                                    |  | 1,680,000    |  |                           | 1,680  |  |                        | 1,678,320   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 1,680,000   |  
|Stock issuance cost charged to additional paid-in capital                                   |  |             |  |                           |       |  |                        | (168,000    | ) |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | (168,000    | )
|Net loss for period from inception to September 30, 2003                                    |  |             |  |                           |       |  |                        |            |   |                                              |   |         |                        |  |   | (95,238      | ) |  |   |          |   |  |   | (95,238     | )
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Balance at September 30, 2003                                                               |  | 4,680,000    |  |                           | 4,680  |  |                        | 1,510,320   |   |                                              |   |         |                        |  |   | (95,238      | ) |  |   |          |   |  |   | 1,419,762   |  
|Exercise of stock options                                                                   |  | 75,000       |  |                           | 75     |  |                        | 14,925      |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 15,000      |  
|Common stock & warrants issued for cash @ $1.00 per unit                                    |  | 475,000      |  |                           | 475    |  |                        | 474,525     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 475,000     |  
|Common stock & warrants issued for marketable securities @ $1.00 per unit                   |  | 500,000      |  |                           | 500    |  |                        | 499,500     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 500,000     |  
|Stock issuance cost charged to additional paid-in capital                                   |  |             |  |                           |       |  |                        | (96,500     | ) |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | (96,500     | )
|Common stock and warrants issued for cash @ $1.50 per unit                                  |  | 6,608,788    |  |                           | 6,609  |  |                        | 9,906,573   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 9,913,182   |  
|Common stock issued in reverse acquisition                                                  |  | 705,529      |  |                           | 706    |  |                        | (151,175    | ) |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | (150,469    | )
|Common stock issued as a gift for $1.09 per share                                           |  | 150,000      |  |                           | 163    |  |                        | 162,587     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 162,750     |  
|Common stock and warrants issued as stock issuance cost @ $1.50 per unit                    |  | 356,229      |  |                           | 356    |  |                        | 533,988     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 534,344     |  
|Stock issuance cost charged to additional paid-in capital                                   |  |             |  |                           |       |  |                        | (991,318    | ) |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | (991,318    | )
|Exercise of stock option @ $0.20 per share                                                  |  | 75,000       |  |                           | 75     |  |                        | 14,925      |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 15,000      |  
|Exercise of stock options @ $1.00 per share                                                 |  | 6,000        |  |                           | 6      |  |                        | 5,994       |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 6,000       |  
|Stock-based compensation                                                                    |  |             |  |                           |       |  |                        | 175,653     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 175,653     |  
|Net loss for the year ended September 30, 2004                                              |  |             |  |                           |       |  |                        |            |   |                                              |   |         |                        |  |   | (2,528,954   | ) |  |   | 1,777,699 |   |  |   | (751,255    | )
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Balance at September 30, 2004                                                               |  | 13,631,546   |  |                           | 13,645 |  |                        | 12,059,997  |   |                                              |   |         |                        |  |   | (2,624,192   | ) |  |   | 1,777,699 |   |  |   | 11,227,149  |  
|Exercise of warrants @ $1.50 per share                                                      |  | 13,812,888   |  |                           | 13,813 |  |                        | 20,705,522  |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 20,719,335  |  
|Exercise of stock options @ $1.00 per share                                                 |  | 25,000       |  |                           | 25     |  |                        | 24,975      |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 25,000      |  
|Common stock issued to purchase Insert Therapeutics share @ $3.98 per share                 |  | 502,260      |  |                           | 502    |  |                        | 1,999,498   |   |                                              |   |         |                        |  |   |             |   |  |   |           |   |  |   | 2,000,000   |  
|Common stock issued for services                                                            |  | 12,500       |  |                           | 12     |  |                        | 49,988      |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 50,000      |  
|Stock-based compensation                                                                    |  |             |  |                           |       |  |                        | 508,513     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 508,513     |  
|Change in percentage of ownership in subsidiary                                             |  |             |  |                           |       |  |                        | 230,087     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 230,087     |  
|Net loss for the year ended September 30, 2005                                              |  |             |  |                           |       |  |                        |            |   |                                              |   |         |                        |  |   | (6,854,918   | ) |  |   | 121,491   |   |  |   | (6,733,427  | )
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Balance at September 30, 2005                                                               |  | 27,984,194   |  |                           | 27,997 |  |                        | 35,578,580  |   |                                              |   |         |                        |  |   | (9,479,110   | ) |  |   | 1,899,190 |   |  |   | 28,026,657  |  
|Exercise of stock options                                                                   |  | 115,794      |  |                           | 116    |  |                        | 341,421     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 341,537     |  
|Common stock issued @ $4.88 per share                                                       |  | 204,854      |  |                           | 205    |  |                        | 999,795     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 1,000,000   |  
|Common stock issued @ $3.84 per share                                                       |  | 15,000       |  |                           | 15     |  |                        | 57,585      |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 57,600      |  
|Common stock issued @ $3.50 per share                                                       |  | 5,590,000    |  |                           | 5,590  |  |                        | 19,539,410  |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 19,545,000  |  
|Common stock issued @ $5.91 per share                                                       |  | 25,364       |  |                           | 25     |  |                        | 149,975     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 150,000     |  
|Common stock issued to purchase Calando Pharmaceuticals, Inc. @ $5.17 per share             |  | 208,382      |  |                           | 208    |  |                        | 1,077,125   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 1,077,333   |  
|Stock-based compensation                                                                    |  |             |  |                           |       |  |                        | 1,369,478   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 1,369,478   |  
|Net loss for the year ended September 30, 2006                                              |  |             |  |                           |       |  |                        |            |   |                                              |   |         |                        |  |   | (18,997,209  | ) |  |   | (964,752  | ) |  |   | (19,961,961 | )
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Balance at September 30, 2006                                                               |  | 34,143,588   |  |                           | 34,156 |  |                        | 59,113,369  |   |                                              |   |         |                        |  |   | (28,476,319  | ) |  |   | 934,438   |   |  |   | 31,605,644  |  
|Exercise of stock options                                                                   |  | 186,164      |  |                           | 186    |  |                        | 434,541     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 434,727     |  
|Common stock issued @ $5.78 per share, net                                                  |  | 2,849,446    |  |                           | 2,849  |  |                        | 15,149,366  |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 15,152,215  |  
|Arrowheads increase in proportionate share of Insert Therapeutics equity                  |  |             |  |                           |       |  |                        | 2,401,394   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 2,401,394   |  
|Common stock issued for purchase of Carbon Nanotechnologies, Inc. @ $3.77 per share         |  | 1,431,222    |  |                           | 1,431  |  |                        | 5,398,569   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 5,400,000   |  
|Stock-based compensation                                                                    |  |             |  |                           |       |  |                        | 2,175,544   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 2,175,544   |  
|Net loss for the year ended September 30, 2007                                              |  |             |  |                           |       |  |                        |            |   |                                              |   |         |                        |  |   | (29,931,118  | ) |  |   | (781,829  | ) |  |   | (30,712,947 | )
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Balance at September 30, 2007                                                               |  | 38,610,420   |  |                           | 38,622 |  |                        | 84,672,783  |   |                                              |   |         |                        |  |   | (58,407,437  | ) |  |   | 152,609   |   |  |   | 26,456,577  |  
|Exercise of stock options                                                                   |  | 105,357      |  |                           | 106    |  |                        | 289,921     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 290,027     |  
|Common stock issued at approximately $1.80 per share, net                                   |  | 3,863,989    |  |                           | 3,867  |  |                        | 6,956,718   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 6,960,585   |  
|Arrowheads increase in proportionate share of Unidyms equity                              |  |             |  |                           |       |  |                        | 1,720,962   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 1,720,962   |  
|Common stock issued @ $2.72 per share to Rice University                                    |  | 50,000       |  |                           | 50     |  |                        | 135,950     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 136,000     |  
|Common stock issued @ $2.83 per share to purchase shares of Unidym, Inc.                    |  | 70,547       |  |                           | 71     |  |                        | 199,929     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 200,000     |  
|Common stock issued @ $2.95 per share to purchase MASA Energy, LLC                          |  | 105,049      |  |                           | 105    |  |                        | 309,895     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 310,000     |  
|Common stock issued @ $2.19 per share to Unidym for the acquisition of Nanoconduction       |  | 114,155      |  |                           | 114    |  |                        | 249,886     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 250,000     |  
|Common stock issued @ $2.18 per share                                                       |  | 15,000       |  |                           | 15     |  |                        | 32,685      |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 32,700      |  
|Stock-based compensation                                                                    |  |             |  |                           |       |  |                        | 3,187,397   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 3,187,397   |  
|Net loss for the year ended September 30, 2008                                              |  |             |  |                           |       |  |                        |            |   |                                              |   |         |                        |  |   | (27,089,030  | ) |  |   | (152,609  | ) |  |   | (27,241,639 | )
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Balance at September 30, 2008                                                               |  | 42,934,517   |  |                           | 42,950 |  |                        | 97,756,126  |   |                                              |   |         |                        |  |   | (85,496,467  | ) |  |   |          |   |  |   | 12,302,609  |  
|Common Stock issued @ $0.55 per share to Unidym stockholder in exchange for Unidyms shares |  | 2,058,393    |  |                           | 2,059  |  |                        | 1,131,617   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 1,133,676   |  
|Common Stock issued @ $0.52 per share to TEL Ventures in exchange for Unidyms shares       |  | 2,222,222    |  |                           | 2,222  |  |                        | 1,156,111   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 1,158,333   |  
|Reclassification of former Unidym mezzanine debt to equity                                  |  |             |  |                           |       |  |                        | 2,000,000   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 2,000,000   |  
|Arrowheads increase in proportionate share of Calandos equity                             |  |             |  |                           |       |  |                        | 2,120,250   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 2,120,250   |  
|Common stock issued @ $0.30 per share                                                       |  | 9,196,642    |  |                           | 9,197  |  |                        | 2,749,796   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 2,758,993   |  
|Change in percentage of ownership in subsidiary                                             |  |             |  |                           |       |  |                        | 16,297      |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 16,297      |  
|Stock-based compensation                                                                    |  |             |  |                           |       |  |                        | 2,676,170   |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 2,676,170   |  
|Issuance of Series D Preferred Stock for Subscription in Unidym                             |  |             |  |                           |       |  |                        | 300,000     |   |                                              |   | (300,000 | )                      |  |   |             |   |  |   |          |   |  |   |            |  
|Amortization of discount on Unidym Series D Preferred Stock                                 |  |             |  |                           |       |  |                        | 163,960     |   |                                              |   |         |                        |  |   | (163,960     | ) |  |   |          |   |  |   |            |  
|Net loss for the year ended September 30, 2009                                              |  |             |  |                           |       |  |                        |            |   |                                              |   |         |                        |  |   | (19,308,392  | ) |  |   |          |   |  |   | (19,308,392 | )
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Balance at September 30, 2009                                                               |  | 56,411,774   |  |                           | 56,428 |  |                        | 110,070,327 |   |                                              |   | (300,000 | )                      |  |   | (104,968,819 | ) |  |   |          |   |  |   | 4,857,936   |  
|Issuance of Series D Preferred Stock for Subscription in Unidym                             |  |             |  |                           |       |  |                        |            |   |                                              |   | 300,000  |                        |  |   |             |   |  |   |          |   |  |   | 300,000     |  
|Common stock issued @ $0.63 per share                                                       |  | 5,083,430    |  |                           | 5,083  |  |                        | 3,217,813   |   |                                              |   |          |                        |  |   |             |   |  |   |          |   |  |   | 3,222,896   |  
|Common Stock issued to Calando stockholders in exchange for Calandos shares                |  | 1,220,000    |  |                           | 1,220  |  |                        | (160,667    | ) |                                              |   |         |                        |  |   |             |   |  |   | 159,447   |   |  |   |            |  
|Common Stock issued to Unidym stockholders in exchange for Unidyms shares                  |  | 153,176      |  |                           | 153    |  |                        | (1,435      | ) |                                              |   |         |                        |  |   |             |   |  |   | 1,282     |   |  |   |            |  
|Stock-based compensation                                                                    |  |             |  |                           |       |  |                        | 598,230     |   |                                              |   |         |                        |  |   |             |   |  |   |          |   |  |   | 598,230     |  
|Exercise of warrants                                                                        |  | 1,045,373    |  |                           | 1,045  |  |                        | 457,288     |   |                                              |   |         |                        |  |   |             |   |  |   | 200       |   |  |   | 458,533     |  
|Net loss for the six month period ended March 31, 2010                                      |  |             |  |                           |       |  |                        |            |   |                                              |   |         |                        |  |   | (3,398,887   | ) |  |   | (560,139  | ) |  |   | (3,959,026  | )
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  
|Balance at March 31, 2010                                                                   |  | 63,913,753   |  |                           | 63,929 |  |                        | 114,181,556 |   |                                              |   |         |                        |  |   | (108,367,706 | ) |  |   | (399,210  | ) |  |   | 5,478,569   |  
|                                                                                            |  |              |  |                           |        |  |                        |             |   |                                              |   |          |                        |  |   |              |   |  |   |           |   |  |   |             |  



3



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##### Table of Contents

Arrowhead Research Corporation and Subsidiaries

( A Development Stage Company )

Consolidated Statements of Cash Flows

(unaudited)



|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|---------------------------------------------------------------------------- |  | ------------------------- | ---------- | - | ------------------------- | - | ----------- | ----------------------------------------------- |  | - | ------------ | -
|                                                                             |  | Six Months Ended3/31/2010 |            |   | Six Months Ended3/31/2009 |   |             | May 7, 2003(Date of inception) toMarch 31, 2010 | 
|CASH FLOWS FROM OPERATING ACTIVITIES:                                        |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Net Loss                                                                     |  | $                         | (3,959,026 | ) |                           | $ | (13,319,807 | )                                               |  | $ | (124,051,623 | )
|Plus: Net loss attributable to noncontrolling interests                      |  |                           | 560,139    |   |                           |   | 60          |                                                 |  |   | 15,847,877   |  
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Net loss attributable to Arrowhead                                           |  |                           | (3,398,887 | ) |                           |   | (13,319,747 | )                                               |  |   | (108,203,746 | )
|(Income)/loss from discontinued operation                                    |  |                           | (414,796   | ) |                           |   | 115,764     |                                                 |  |   | 6,792,296    |  
|Realized and unrealized gain on investment                                   |  |                           |           |   |                           |   | (700,000    | )                                               |  |   | (1,082,263   | )
|Gain from sale of subsidiary                                                 |  |                           |           |   |                           |   |            |                                                 |  |   | (306,344     | )
|Loss on sale/donation of fixed assets                                        |  |                           |           |   |                           |   |            |                                                 |  |   | 77,374       |  
|Stock issued as gift to Caltech                                              |  |                           |           |   |                           |   |            |                                                 |  |   | 162,750      |  
|Stock issued as gift to Rice University                                      |  |                           |           |   |                           |   |            |                                                 |  |   | 136,000      |  
|Stock issued for professional services                                       |  |                           |           |   |                           |   |            |                                                 |  |   | 232,700      |  
|Stock issued for in-process research and development                         |  |                           |           |   |                           |   |            |                                                 |  |   | 13,166,347   |  
|Change in percentage of ownership in subsidiary                              |  |                           |           |   |                           |   |            |                                                 |  |   | 16,297       |  
|Purchased in-process research and developmentNanoconduction                 |  |                           |           |   |                           |   |            |                                                 |  |   | 2,685,208    |  
|Stock-based compensation                                                     |  |                           | 598,230    |   |                           |   | 1,423,209   |                                                 |  |   | 10,690,985   |  
|Depreciation and amortization                                                |  |                           | 346,726    |   |                           |   | 526,852     |                                                 |  |   | 5,084,371    |  
|Gain on sale of stock in subsidiary                                          |  |                           |           |   |                           |   |            |                                                 |  |   | (2,292,800   | )
|Non-cash loss from equity investment                                         |  |                           | 99,238     |   |                           |   | 129,412     |                                                 |  |   | 439,771      |  
|Noncontrolling interest                                                      |  |                           | (560,139   | ) |                           |   | (60         | )                                               |  |   | (16,848,065  | )
|Gain on renegotiation of accrued severance                                   |  |                           |           |   |                           |   |            |                                                 |  |   | (726,500     | )
|(Increase) decrease of cash flow from:                                       |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Receivables                                                                  |  |                           | (25,063    | ) |                           |   | (82,195     | )                                               |  |   | (173,160     | )
|Prepaid research expense                                                     |  |                           |           |   |                           |   |            |                                                 |  |   | (1           | )
|Other prepaid expenses                                                       |  |                           | 90,967     |   |                           |   | (70,500     | )                                               |  |   | (227,584     | )
|Deposits                                                                     |  |                           | 4,923      |   |                           |   | 25,475      |                                                 |  |   | (106,785     | )
|Accounts payable                                                             |  |                           | (128,993   | ) |                           |   | 659,886     |                                                 |  |   | 252,019      |  
|Accrued expenses                                                             |  |                           | (12,916    | ) |                           |   | 198,103     |                                                 |  |   | 17,625       |  
|Accrued severance and other liabilities                                      |  |                           | 7,690      |   |                           |   | (168,450    | )                                               |  |   | 935,725      |  
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|NET CASH USED IN OPERATING ACTIVITIES OF CONTINUING OPERATIONS               |  |                           | (3,393,020 | ) |                           |   | (11,262,251 | )                                               |  |   | (89,277,780  | )
|CASH FLOWS FROM INVESTING ACTIVITIES OF CONTINUING OPERATIONS:               |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Purchase of marketable securitiesUS Treasury Bills                          |  |                           |           |   |                           |   |            |                                                 |  |   | (18,575,915  | )
|Purchase of property and equipment                                           |  |                           |           |   |                           |   | (28,100     | )                                               |  |   | (3,550,518   | )
|Purchase of MASA Energy, LLC                                                 |  |                           |           |   |                           |   |            |                                                 |  |   | (250,000     | )
|Minority equity investment                                                   |  |                           |           |   |                           |   |            |                                                 |  |   | (2,000,000   | )
|Cash paid for interest in Nanotechnica                                       |  |                           |           |   |                           |   |            |                                                 |  |   | (4,000,000   | )
|Cash paid for interest in Aonex                                              |  |                           |           |   |                           |   |            |                                                 |  |   | (5,000,000   | )
|Cash paid for interest in Insert                                             |  |                           |           |   |                           |   |            |                                                 |  |   | (10,150,000  | )
|Cash paid for interest in Calando                                            |  |                           |           |   |                           |   |            |                                                 |  |   | (8,800,000   | )
|Cash paid for interest in Unidym                                             |  |                           |           |   |                           |   | (225,000    | )                                               |  |   | (14,138,003  | )
|Cash paid/obtained for interest in Tego                                      |  |                           |           |   |                           |   | 1,700,000   |                                                 |  |   | (801,000     | )
|Cash obtained from interest in Nanotechnica                                  |  |                           |           |   |                           |   |            |                                                 |  |   | 4,000,000    |  
|Cash obtained from interest in Aonex                                         |  |                           |           |   |                           |   |            |                                                 |  |   | 5,001,250    |  
|Cash obtained from interest in Insert                                        |  |                           |           |   |                           |   |            |                                                 |  |   | 10,529,594   |  
|Cash obtained from interest in Calando                                       |  |                           |           |   |                           |   |            |                                                 |  |   | 8,800,000    |  
|Cash obtained from interest in Unidym                                        |  |                           |           |   |                           |   | 225,000     |                                                 |  |   | 14,138,003   |  
|Cash paid/obtained from interest in Tego                                     |  |                           |           |   |                           |   | (1,700,000  | )                                               |  |   | 801,000      |  
|Proceeds from sale of marketable securitiesUS Treasury Bills                |  |                           |           |   |                           |   |            |                                                 |  |   | 18,888,265   |  
|Proceeds from sale of investments                                            |  |                           |           |   |                           |   | 700,000     |                                                 |  |   | 1,269,913    |  
|Proceeds from sale of subsidiary (net)                                       |  |                           |           |   |                           |   |            |                                                 |  |   | 359,375      |  
|Proceeds from sale of fixed assets                                           |  |                           |           |   |                           |   | 50,554      |                                                 |  |   | 79,375       |  
|Payment for patents                                                          |  |                           |           |   |                           |   |            |                                                 |  |   | (303,440     | )
|Restricted cash                                                              |  |                           |           |   |                           |   |            |                                                 |  |   | 50,773       |  
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|NET CASH PROVIDED BY (USED IN) INVESTING ACTIVITIES OF CONTINUING OPERATIONS |  |                           |           |   |                           |   | 722,454     |                                                 |  |   | (3,651,328   | )
|CASH FLOWS FROM FINANCING ACTIVITIES OF CONTINUING OPERATIONS:               |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Payments of capital leases                                                   |  |                           | (430,115   | ) |                           |   | (397,151    | )                                               |  |   | (1,380,581   | )
|Proceeds from issuance of Calando debt                                       |  |                           |           |   |                           |   | 2,516,467   |                                                 |  |   | 2,516,467    |  
|Proceeds from sale of stock in subsidiary                                    |  |                           |           |   |                           |   | 2,000,000   |                                                 |  |   | 18,575,168   |  
|Proceeds from issuance of common stock and warrants, net                     |  |                           | 3,981,159  |   |                           |   |            |                                                 |  |   | 82,603,394   |  
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|NET CASH PROVIDED BY FINANCING ACTIVITIES OF CONTINUING OPERATIONS           |  |                           | 3,551,044  |   |                           |   | 4,119,316   |                                                 |  |   | 102,314,448  |  
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Cash flows from discontinued operations:                                     |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Operating cash flows                                                         |  |                           | (15,204    | ) |                           |   | (115,764    | )                                               |  |   | (7,581,671   | )
|Investing cash flows                                                         |  |                           | 430,000    |   |                           |   |            |                                                 |  |   | 789,375      |  
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Net cash provided by (used in) discontinued operations:                      |  |                           | 414,796    |   |                           |   | (115,764    | )                                               |  |   | (6,792,296   | )
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|NET INCREASE (DECREASE) IN CASH                                              |  |                           | 572,820    |   |                           |   | (6,536,245  | )                                               |  |   | 2,593,044    |  
|CASH AT BEGINNING OF PERIOD                                                  |  |                           | 2,020,224  |   |                           |   | 10,093,585  |                                                 |  |   |             |  
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|CASH AT END OF PERIOD                                                        |  | $                         | 2,593,044  |   |                           | $ | 3,557,340   |                                                 |  | $ | 2,593,044    |  
|                                                                             |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Supplementary disclosures:                                                   |  |                           |            |   |                           |   |             |                                                 |  |   |              |  
|Interest paid                                                                |  | $                         | 21,948     |   |                           | $ | 52,264      |                                                 |  | $ | 120,462      |  

The accompanying
notes are an integral part of these unaudited consolidated financial statements.



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SUPPLEMENTAL NON-CASH TRANSACTIONS

On March 23, 2005, Arrowhead Research Corporation (Arrowhead) purchased 7,375,000 shares of Insert Therapeutics, Inc.
(Insert) Common Stock from two minority stockholders of Insert for 502,260 newly issued shares of Arrowhead Common Stock valued at $2,000,000 based on the closing market price of Arrowhead Common Stock on NASDAQ on the date of the
closing.

On March 31, 2006, Arrowhead purchased 964,000 shares of Calando Pharmaceuticals, Inc. (Calando)
Common Stock from minority stockholders of Calando for $1,928,000 consisting of 208,382 newly issued shares of Arrowhead Common Stock valued at $1,077,333 plus $850,667 in cash. The 208,382 shares of Arrowhead Common Stock were valued based on the
average closing price of Arrowheads Common Stock on NASDAQ the ten trading days immediately prior to the date of the closing.

On April 20, 2007, Arrowhead purchased the Series E Preferred Stock of Carbon Nanotechnologies, Inc. in exchange for 1,431,222
shares of Arrowhead Common Stock with an estimated fair market value of $5,400,000 based on the average closing price of Arrowheads Common Stock on NASDAQ the ten trading days immediately prior to March 24, 2007, as set forth in the
Agreement and Plan of Merger among Unidym, Inc. (Unidym), Carbon Nanotechnologies, Inc., Arrowhead and others.

On
April 23, 2008, Arrowhead purchased 200,000 shares of the Common Stock of Unidym in exchange for 70,547 shares of Arrowhead Common Stock with an estimated fair market value of $200,000 based on the average closing price of Arrowheads
Common Stock on NASDAQ the ten trading days immediately prior to the date of the closing.

On April 29, 2008, Arrowhead
purchased all of the membership units of MASA Energy, LLC for $560,000. The purchase price consisted of 105,049 shares of Arrowhead Common Stock with an estimated fair market value of $310,000 based on the average closing price of Arrowheads
Common Stock on NASDAQ the ten trading days immediately prior to the date of the closing, plus $250,000 in cash.

On
August 8, 2008, Unidym acquired all of the outstanding stock of Nanoconduction, Inc. in exchange for 114,115 shares of Arrowhead Common Stock with an estimated fair market value of $250,000.

On June 11, 2009, Arrowhead issued 1,324,625 shares of Common Stock with an estimated fair market value of $688,802 in exchange for
an equal number of Series A Preferred Stock of Unidym, with minority stockholders of Unidym.

On June 25, 2009, Arrowhead
issued 1,944,444 shares of Common Stock with an estimated fair market value of $972,222 in exchange for an equal number of Series C Preferred Stock of Unidym, with a minority stockholder of Unidym.

On September 22, 2009, Arrowhead issued 91,495 shares of Common Stock with an estimated fair market value of $46,662 in exchange for
an equal number of Series A Preferred Stock of Unidym with a minority stockholder of Unidym.

On September 28, 2009,
Arrowhead issued 642,273 shares of Common Stock with an estimated fair market value of $398,209 in exchange for 5,574 shares of Series A Preferred Stock and 636,699 shares of Series C Preferred Stock of Unidym, with several minority stockholders of
Unidym.

On September 30, 2009, Arrowhead issued 277,778 shares of Common Stock with an estimated fair market value of
$186,111 in exchange for an equal number of shares of Series C-1 Preferred Stock of Unidym, with a minority stockholder of Unidym.

In October and November 2009, Arrowhead issued 153,176 shares of Common Stock with an estimated fair market value of $47,485 in exchange
for an equal number of shares of Series C Preferred Stock of Unidym, with several minority stockholders of Unidym.

In October
and November 2009, Arrowhead issued 1,140,000 shares of Common Stock with an estimated fair market value of $706,800 in exchange for 2,850,000 shares of Calando common stock, with several minority stockholders of Calando. In conjunction with the
exchange, Arrowhead also issued 240,000 Warrants to purchase Arrowhead Common Stock in exchange for 600,000 Warrants to purchase Calando Common Stock.

In March 2010, a warrant holder exercised 247,880 warrants to purchase Arrowhead Common Stock, in a cashless exercise, whereby Arrowhead
issued to the warrant holder 128,707 shares of Arrowhead Common Stock.

The accompanying notes are an integral part of these
unaudited consolidated financial statements



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Arrowhead Research Corporation

Notes to Consolidated Financial Statements

(Unaudited)

Unless
otherwise noted, (1) the term Arrowhead refers to Arrowhead Research Corporation, a Delaware corporation formerly known as InterActive Group, Inc., (2) the terms the Company, we, us, and
our refer to the ongoing business operations of Arrowhead and its Subsidiaries, whether conducted through Arrowhead or a subsidiary of Arrowhead, (3) the term ARC refers to Arrowhead Research Corporation, a
privately-held California corporation with which Arrowhead consummated a stock exchange transaction in January 2004, (4) the term Subsidiaries refers collectively to Calando Pharmaceuticals, Inc. (Calando), Unidym, Inc.
(Unidym), Agonn Systems, Inc. (Agonn,) and Tego Biosciences Corporation (Tego) and (5) the term Common Stock refers to Arrowheads Common Stock, $0.001 par value per share, and the term
stockholder(s) refers to the holders of Common Stock or securities exercisable for Common Stock.

NOTE 1.ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES

Nature of Business

Arrowhead Research Corporation is a development stage nanotechnology holding company that forms, acquires and operates subsidiaries
commercializing innovative nanotechnologies. By working closely with leading scientists and universities, Arrowhead identifies advances in nanotechnology and matches them with product development opportunities in high-growth markets. The Company is
currently focused on the electronics and biotech industries. Arrowhead owns two majority-owned subsidiaries, Unidym and Calando, and has minority investments in two early-stage nanotechnology companies, Nanotope, Inc. (Nanotope) and
Leonardo Biosystems, Inc. (Leonardo).

Arrowhead is incorporated in Delaware and its principal executive offices
are located in Pasadena, California.

The Company was originally incorporated in South Dakota in 1989, and was reincorporated
in Delaware in 2000. The Companys principal executive offices are located at 201 South Lake Avenue, Suite 703, Pasadena, California 91101, and its telephone number is (626) 304-3400. As of March 31, 2010, Arrowhead Research
Corporation had eleven full-time employees at the corporate office and eight full-time employees at its Subsidiary companies.

Financing
and Liquidity

At March 31, 2010, the Company had approximately $2.6 million in cash to fund operations. Arrowhead has
historically financed its operations through the sale of securities of Arrowhead and its Subsidiaries. During fiscal 2009, the Company obtained $7.3 million in cash through equity and debt financing, including $2.5 million raised by Calando through
the sale of senior unsecured convertible promissory notes, and $2.0 million raised by Unidym through the sale of newly issued shares of Series C-1 Preferred Stock. Also during fiscal 2009, the Company obtained an additional $4.4 million from the
sales of assets, products and license fees, including the sale by Unidym of its equity interest in Ensysce BioSciences Inc. for $700,000. During the first half of fiscal 2010, the Company received $3.5 million in cash through an equity financing,
$0.5 million from the exercise of warrants, and $0.7 million from revenue and asset sales, including the sale of the Tego IP. The company anticipates that further equity financings, and/or asset sales and license agreements will be necessary to
continue to fund operations.

The Companys strategic plan includes focusing on near term revenue opportunities,
conserving cash and seeking sources of new capital. To execute this plan, the Company will seek to accomplish one or more of the following on favorable terms: the out-license of technology, sale of a subsidiary, sale of non-core assets, scaling down
development efforts, funded joint development or partnership arrangements and sale of securities. The likelihood that any of these events will occur is uncertain, especially in light of the lack of liquidity in the current capital and credit
markets. Until such time as one or more of these goals is accomplished, the Company has scaled back the activities at its Subsidiaries.



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Summary of Significant Accounting Policies

Principles of ConsolidationThe consolidated financial statements of the Company include the accounts of Arrowhead and its
wholly-owned and majority-owned Subsidiaries. Prior to April 2008, Arrowheads Subsidiaries included Insert Therapeutics, Inc. (Insert), which was merged with Calando in April 2008. The merged entity is majority-owned by Arrowhead
and continues to operate under the name of Calando. At March 31, 2010, other Subsidiaries included Unidym, Tego, and Agonn. On December 23, 2009, Tego completed a sale of its assets to Luna Innovations, Inc. and is included in the results
as Loss from Discontinued Operations. Loss from Discontinued Operations also includes Aonex Technologies, Inc. (Aonex), sold in May 2008 and Nanotechnica, Inc. (Nanotechnica), dissolved in June 2005. All significant
intercompany accounts and transactions are eliminated in consolidation, and noncontrolling interests are accounted for in the consolidated statements of operations and the balance sheets.

Basis of Presentation and Use of EstimatesThe preparation of financial statements in conformity with generally accepted accounting
principles requires management to make estimates and assumptions that affect the amounts reported in the accompanying financial statements. Significant estimates made in preparing these financial statements include valuing of the stock of the
Subsidiaries, assumptions to calculate stock-based compensation expense, allowance for doubtful accounts, deferred tax asset valuation allowance, derivative liabilities, noncontrolling interest and useful lives for depreciable and amortizable
assets. Actual results could differ from those estimates. Additionally, certain reclassifications have been made to prior period financial statements to conform to the current period presentation. In the opinion of management, all adjustments,
including normal recurring accruals considered necessary for a fair presentation, have been included.

Cash and Cash
EquivalentsThe Company considers all liquid debt instruments purchased with a maturity of three months or less to be cash equivalents.

Credit RiskThe Company extends credit to its customers in the normal course of business and generally does not require collateral
or other security. The Company performs ongoing credit evaluations of its customers financial condition and historically has not incurred significant credit losses.

Concentration of Credit RiskThe Company maintains checking accounts for Arrowhead and separate accounts for each Subsidiary at any
of three financial institutions. These accounts are insured by the Federal Deposit Insurance Corporation (FDIC) for up to $250,000 per account. The Company has two wealth management accounts at the same financial institutions that invest in higher
yield money market accounts and in government securities. At March 31, 2010, the Company had uninsured cash deposits totaling $2,275,464. The Company has not experienced any losses in such accounts.

Property and EquipmentProperty and equipment are recorded at cost. Depreciation of property and equipment is recorded using the
straight-line method over the respective useful lives of the assets ranging from three to seven years. Leasehold improvements are amortized over the lesser of the expected useful life or the remaining lease term.

Intellectual PropertyAt March 31, 2010, intellectual property consisted of patents and patent applications licensed or
purchased in the gross amount of $4,093,624. The accumulated amortization of patents totaled $1,888,976 at March 31, 2010. Patents are amortized over three years to twenty years. The weighted average original amortization period is twelve
years. The weighted average remaining amortization period is eight years. Amortization is expected to be $157,812 for the remainder of fiscal 2010, $315,624 in fiscal 2011, and $241,808 for fiscal years 2012, 2013, and 2014. Long-lived assets, such
as property, equipment and intangible assets subject to amortization, are reviewed for impairment whenever events or circumstances indicate that the carrying amount of these assets may not be recoverable. In reviewing for impairment, we compare the
carrying value of such assets to the estimated undiscounted future cash flows expected from the use of the assets and their eventual disposition. When the estimated undiscounted future cash flows are less than their carrying amount, an
impairment loss is recognized equal to the difference between the assets fair value and their carrying value.

Equity
InvestmentsArrowhead has a non-controlling equity investment in Nanotope, a privately held biotechnology company, which is recorded in Other Assets. This investment is carried at cost less Arrowheads proportionate share of
Nanotopes operating loss for the period since investment because Arrowhead owns more than 20% of the voting equity and has the ability to exercise significant influence over this company. This investment is high-risk as the markets for
technologies or products of Nanotope are still in the development stage and such markets may never be significant. Arrowhead could lose its entire investment in Nanotope. Arrowhead monitors this investment for impairment and makes appropriate
reductions in carrying value when necessary.

Minority Equity InvestmentsThe Companys minority equity investment
in Leonardo, a privately held biotechnology company, is recorded in Other Assets. This investment is accounted for under the cost method of accounting, because Arrowhead owns less than 20% of the voting equity and only has the ability to exercise
nominal, not significant, influence over this company. This investment is high risk as the markets for technologies or products of Leonardo are still in the development stage and such markets may never be significant. Arrowhead could lose its entire
investment in some or all of this company. Arrowhead monitors this investment for impairment and makes appropriate reductions in carrying value when necessary.



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Noncontrolling Interests in Majority-Owned SubsidiariesOperating losses applicable to
majority-owned Calando and Unidym have periodically exceeded the noncontrolling interests in the equity capital of either subsidiary. Such excess losses applicable to the noncontrolling interests have been and are borne by the Company as there is no
obligation of the noncontrolling interests to fund any losses in excess of their original investment. There is also no obligation or commitment on the part of the Company to fund operating losses of any subsidiary whether wholly-owned or
majority-owned. The Company allocates the noncontrolling interests share of net loss in excess of the noncontrolling interests initial investment in accordance with FASB ASC 810-10, which was effective for the Company on October 1,
2009.

When there is a change in the Companys proportionate share of a development-stage subsidiary resulting from
additional equity raised by the subsidiary, the change is accounted for as an equity transaction in consolidation. To the extent that the increase in the calculated value of the Companys interest in the equity of the subsidiary exceeds the
Companys investment in the offering, that increase in value is referred to as the Companys increase in its proportionate share of the subsidiarys equity and the amount is recorded as an increase in the Companys
Additional Paid-in Capital.

When Insert raised $10.1 million in October 2006, Arrowhead participated by investing $5.0
million in the offering. In comparison, the value of Arrowheads equity in Insert increased by $7,401,394. Consistent with the guidance found in Staff Accounting Bulletin Topic 5H, as codified in FASB ASC 505-10-S99-6, the difference between
the amount invested by Arrowhead and the increase in Arrowheads equity value in the subsidiary, or $2,401,394, was recorded as an increase in Arrowheads proportionate share of the subsidiarys equity and is shown as an
increase in the Companys Additional Paid-in Capital. A similar calculation was made for the Unidym $10.0 million offering in the fall of 2007. Arrowhead contributed $3.0 million but the value of its interest in the equity of Unidym increased
by $4,720,962. The $1,720,962 difference was recorded as an increase in Arrowheads proportionate share of the subsidiarys equity and is shown as an increase in the Companys Additional Paid-in Capital.

Revenue RecognitionRevenue from product sales are recorded when persuasive evidence of an arrangement exists, title has passed and
delivery has occurred, a price is fixed and determinable, and collection is reasonably assured. We may generate revenue from product sales, technology licenses, collaborative research and development arrangements, and research grants. Revenue under
technology licenses and collaborative agreements typically consists of nonrefundable and/or guaranteed technology license fees, collaborative research funding and various milestone and future product royalty or profit-sharing payments.

Revenue associated with research and development funding payments, under collaborative agreements, is recognized ratably over the
relevant periods specified in the agreement, generally the research and development period. Revenue from up-front license fees and milestones and product royalties are recognized as earned based on the completion of the milestones and product sales,
as defined in the respective agreements. Payments received in advance of recognition as revenue are recorded as deferred revenue.

Cost of Goods SoldThe production of nanotubes by Unidym has been primarily for research and development activities. Therefore, the
nanotubes produced are not capitalized as inventory, nor is a cost of goods sold calculated, even though some nanotubes are eventually sold to third parties.

Allowance for Doubtful AccountsThe Company accrues an allowance for doubtful accounts based on estimates of uncollectible revenues
by analyzing historical collections, accounts receivable aging and other factors. Accounts receivable are written off when all collection attempts have failed.

Research and DevelopmentCosts and expenses that can be clearly identified as research and development are charged to expense as
incurred in accordance with FASB ASC 718-10.

Earnings (Loss) per ShareBasic earnings (loss) per share is computed using
the weighted-average number of common shares outstanding during the period. Diluted earnings (loss) per share are computed using the weighted-average number of common shares and dilutive potential common shares outstanding during the period.
Dilutive potential common shares primarily consist of stock options issued to employees and consultants and warrants to purchase Common Stock of the Company. These items have been excluded from the loss per share because their effect is
anti-dilutive.

Stock-Based CompensationThe Company accounts for share-based compensation arrangements in accordance
with FASB ASC 718, which requires the measurement and recognition of compensation expense for all share-based payment awards to be based on estimated fair values. We use the Black-Scholes option valuation model to estimate the fair value of our
stock options at the date of grant. The Black-Scholes option valuation model requires the input of subjective assumptions to calculate the value of stock options. We use historical data among other information to estimate the expected price
volatility, the expected option life and the expected forfeiture rate.

Income TaxesThe Company accounts for income
taxes under the liability method, which requires the recognition of deferred income tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. Under this method,
deferred income taxes are recognized for the tax consequences in future years of differences



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between the tax bases of assets and liabilities and their financial reporting amounts at each period end based on enacted tax laws and statutory tax rates applicable to the periods in which the
differences are expected to affect taxable income. Valuation allowances are established, when necessary, to reduce deferred income tax assets to the amount expected to be realized. The provision for income taxes, if any, represents the tax payable
for the period and the change in deferred income tax assets and liabilities during the period.

Recently Issued Accounting Standards

On July 1, 2009, the FASB issued the FASB Accounting Standards Codification (the Codification). The Codification
became the single source of authoritative non-governmental U.S. generally accepted accounting principles (GAAP), superseding existing FASB, American Institute of Certified Public Accountants (AICPA), Emerging Issues Task
Force (EITF) and related literature. The Codification eliminates the previous US GAAP hierarchy and establishes one level of authoritative GAAP. All other literature is considered non-authoritative. The Codification was effective
for interim and annual periods ending after September 15, 2009. The Company adopted the Codification for the year ended September 30, 2009. This guidance did not change GAAP, therefore it did not have an impact on our consolidated
financial statements. References within this note and throughout our financial statements to authoritative guidance issued by the FASB are in reference to the codification.

In January 2010, the FASB issued Accounting Standards Update (ASU) No. 2010-06, Fair Value Measurements and Disclosures
(Topic 820)  Improving Disclosures about Fair Value Measurements. This guidance requires new disclosures related to recurring and nonrecurring fair value measurements. The guidance requires disclosure of transfers of assets and
liabilities between Level 1 and Level 2 of the fair value measurement hierarchy, including the reasons and the timing of the transfers and information on purchases, sales, issuance, and settlements on a gross basis in the reconciliation of the
assets and liabilities measured under Level 3 of the fair value measurement hierarchy. The adoption of this guidance is effective for interim and annual reporting periods beginning after December 15, 2009. We have adopted this guidance in the
financial statements presented herein, which did not impact our consolidated financial position or results of operations.

Recent
Accounting Guidance Not Yet Adopted

Management does not believe that any recently issued, but not yet effective,
accounting standards, if currently adopted, would have a material effect on the accompanying financial statements.

In
June 2009, the FASB issued amendments to the accounting rules for variable interest entities (VIEs) and for transfers of financial assets, codified as ASC 860-10. The new guidance for VIEs eliminates the quantitative approach previously
required for determining the primary beneficiary of a variable interest entity and requires ongoing qualitative reassessments of whether an enterprise is the primary beneficiary. In addition, qualifying special purpose entities (QSPEs)
are no longer exempt from consolidation under the amended guidance. The amendments also limit the circumstances in which a financial asset, or a portion of a financial asset, should be derecognized when the transferor has not transferred the entire
original financial asset to an entity that is not consolidated with the transferor in the financial statements being presented, and/or when the transferor has continuing involvement with the transferred financial asset. This guidance is effective as
of the beginning of a reporting entitys first annual reporting period that begins after November 15, 2009 and for interim periods within the first annual reporting period. The Company does not expect the adoption of these amendments to
have a material impact on the consolidated financial statements.

In June 2009, the FASB issued revised guidance codified
as ASC 860-10, to improve the relevance, representational faithfulness, and comparability of the information that a reporting entity provides in its financial reports about a transfer of financial assets; the effects of a transfer on its financial
position, financial performance, and cash flows; and a transferors continuing involvement in transferred financial assets. This guidance will be effective for fiscal years beginning after November 15, 2009. The Company is currently
evaluating the impact the adoption of these standards will have on its consolidated financial statements and related disclosures.

In June 2009, the FASB issued guidance codified as ASC 470-20, regarding accounting for own-share lending arrangements in
contemplation of convertible debt issuance which changes the accounting for equity share lending arrangements on an entitys own shares when executed in contemplation of a convertible debt offering. This guidance requires the share lending
arrangement to be measured at fair value and recognized as an issuance cost. These issuance costs should then be amortized as interest expense over the life of the financing arrangement. Shares loaned under these arrangements should be excluded from
computation of earnings per share. This guidance is effective for fiscal years beginning after December 15, 2009 and requires retrospective application for all arrangements outstanding as of the beginning of the fiscal year. The Company does
not expect the adoption of this guidance to have a material impact on its consolidated financial statements.

In
October 2009, the FASB issued authoritative guidance on multiple-deliverable revenue arrangements, ASC 605-25. This guidance amends the existing criteria for separating consideration received in multiple-deliverable arrangements and requires
that arrangement consideration be allocated at the inception of the arrangement to all deliverables based on their relative selling price. The guidance establishes a hierarchy for determining the selling price of a deliverable which is based on
vendor-specific objective evidence, third-party evidence, or management estimates. Expanded disclosures related to multiple-deliverable revenue arrangements



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are also required. This guidance is effective for the Company beginning fiscal year 2011, with early adoption permitted. Upon adoption, the guidance may be applied either prospectively from the
beginning of the fiscal year for new or materially modified arrangements, or it may be applied retrospectively. The Company does not expect the adoption of this guidance to have a material impact on its consolidated financial statements.

NOTE 2.BASIS OF CONSOLIDATION

The consolidated financial statements include the accounts of Arrowhead and its Subsidiaries, Calando, Unidym, Tego, and Agonn. All
significant intercompany accounts and transactions are eliminated in consolidation and noncontrolling interests were accounted for in the consolidated financial statements.

NOTE 3.INVESTMENT IN SUBSIDIARIES

Unidym, Inc.

The company
now known as Unidym, Inc. was founded by Arrowhead in 2005. Through the license of intellectual property and the acquisition of three development stage nanotechnology companies in 2006, 2007 and 2008, Unidym acquired the rights to key patents for
the manufacture and application of carbon nanotubes, and is developing products with applications for the display industry. The consolidated financial statements include the results of the merged companies.

Prior to fiscal 2008, Arrowhead invested $4,000,000 in Unidym and provided Arrowhead stock with an aggregate value of $5.65 million to
facilitate two of the acquisitions.

In fiscal 2008, Unidym raised a total of $14.6 million through the sale of Series C
Preferred Stock, of which $5.25 million was invested by Arrowhead. In fiscal 2009, Unidym raised a total of $4.7 million through the sale of Series C-1 Preferred Stock, of which $2.7 million was invested by Arrowhead.

In September 2009, Arrowhead invested $642,000 in exchange for 2,140,000 shares of Unidym Series D Preferred Stock and a warrant to
purchase 3,146,208 shares of Unidym common stock at an exercise price of $0.25 per share with an expiration date three years from the date of issuance. As a condition to this investment, each share of Series C-1 Preferred Stock was converted to six
shares of Unidym Series D Preferred Stock. A minority shareholder of Unidym invested $300,000 for 1,000,000 shares of Unidym Series D Preferred Stock and 1,000,000 warrants with similar terms.

In fiscal 2008 and fiscal 2009, Arrowhead increased its ownership interest in Unidym through a series of stock exchanges with minority
holders of Unidym. In April 2008, Arrowhead acquired 550,000 shares of Unidym common stock from a director and minority holder of Unidym in exchange for $350,000 in cash and restricted Arrowhead Common Stock valued at $200,000. As part of the
agreement, the director resigned from his seat on the Unidym board and the Chief Executive Officer of the Company was appointed to the Unidym board. In transactions in June and September 2009, Arrowhead acquired 1,421,869 shares of Unidym Series A
Preferred Stock, 1,747,810 shares of Unidym Series C Preferred Stock and 1,111,111 shares of Unidym Series C-1 Preferred Stock for an equal number of shares of Arrowhead Common Stock. Each share of Unidym Series A Preferred Stock is convertible into
1.68 shares of Unidym common stock.

In October and November 2009, Arrowhead issued 153,176 shares of Common Stock with an
estimated fair market value of $47,485 in exchange for an equal number of shares of Series C Preferred Stock of Unidym, with several minority stockholders of Unidym.

As of March 31, 2010, Arrowhead owned 80% of the outstanding stock of Unidym and 63% on a fully diluted basis.

Calando Pharmaceuticals, Inc. (formerly known as Insert Therapeutics, Inc.)

On April 17, 2008, Calando merged with and into Insert, with Insert as the surviving company. Prior to the merger, Arrowhead invested
an aggregate of $23.2 million in Calando through the purchase of equity and loans. As a condition of the merger, the Preferred Stock of each of Calando and Insert was converted into common stock and the loans were converted to equity. As a result of
the merger, shares of Insert common stock was issued to the stockholders of the former Calando, and Insert changed its name to Calando Pharmaceuticals, Inc.

On November 26, 2008, Calando entered into Unsecured Convertible Promissory Note Agreements (Notes) for $2.5 million
with accredited investors and Arrowhead, which invested $200,000 in the Notes offering. Arrowhead subsequently invested an additional $600,000 in the same offering. The Notes mature on November 26, 2010 and bear 10% annual interest. The Notes
are convertible into Calando common stock and can be redeemed for two times their face value plus interest in the event of a sale of Calando. To facilitate this investment in Calando, Arrowhead subordinated a series of 6% simple interest loans and
advances totaling approximately $5.3 million of principal plus interest.



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Effective June 23, 2009, to facilitate licensing transactions with a third party,
holders (including Arrowhead) of an aggregate of $2.9 million of the Notes including accrued but unpaid interest, converted the principal and accrued interest into newly authorized Calando Series A Preferred Stock. The non-voting Series A Preferred
Stock has a liquidation preference of 2.5 times the Series A Original Issue Price of $1,000 per share and is convertible into common stock at a conversion price of $0.576647 per share. Arrowhead converted all of its Notes representing a principal
balance of $800,000 plus accrued but unpaid interest into 829 shares of Series A Preferred Stock. One third-party Note for $500,000 plus interest remains outstanding.

As of March 31, 2010, Arrowhead had a series of 6% simple-interest working capital loans and advances outstanding to Calando
totaling $6,645,300, inclusive of accrued interest of $468,597, which are payable upon demand.

In fiscal 2010, Arrowhead
issued 1,220,000 shares of Common Stock in exchange for 3,050,000 shares of Calando common stock, with several minority stockholders of Calando. In conjunction with this exchange, Arrowhead also issued 240,000 warrants to purchase Arrowhead Common
Stock in exchange for 600,000 warrants to purchase Calando common stock.

As of March 31, 2010, Arrowhead owned 70% of
the outstanding shares of Calando and 62% on a fully diluted basis.

Agonn Systems, Inc.

Arrowhead founded Agonn in May 2008 to explore, develop and commercialize nanotechnology-based energy storage devices for electric
vehicles and other large format applications. In line with Arrowheads strategy to conserve cash, Agonn has ceased its development efforts.

Masa Energy LLC

In
April 2008, Arrowhead acquired Masa Energy LLC (Masa) a Delaware limited liability company whose sole assets were an approximate 6% ownership interest in each of Nanotope and Leonardo. During the quarter ended March 31, 2010, the
stockholdings were transferred to Arrowhead and Masa was dissolved.

Nanotope, Inc.

Through the acquisition of Masa, the Company acquired a 5.78% minority position in Nanotope. Nanotope is developing advanced nanomaterials
for the treatment of spinal cord injuries and wound healing. In July and September 2008, Arrowhead acquired 1,801,802 shares of Series B Preferred Stock of Nanotope for two payments of $1 million each, increasing Arrowheads ownership of
Nanotope to approximately 23%. Since inception, Nanotopes revenue has been negligible. Operating expenses for the three and six months ended March 31, 2010 were approximately $239,000 and $454,000, respectively. Nanotopes net loss
for the three and six months ended March 31, 2010 was $230,000 and $445,000, respectively. Arrowhead accounts for its investment in Nanotope using the equity method of accounting.

Leonardo Biosystems, Inc.

Through the acquisition of Masa, Arrowhead acquired a 6.13% ownership interest in Leonardo. Leonardo is developing a drug-delivery
platform technology based on novel methods of designing spheroid porous silicon microparticles that selectively accumulate in tumor vasculature. During the three and six months ended March 31, 2010, Arrowhead incurred expenses of $17,312 and
$20,226, respectively, related to Leonardo. It is expected that the expenses will be repaid or converted into equity. Arrowhead accounts for its investment in Leonardo using the cost method of accounting.

NOTE 4.DISCONTINUED OPERATIONSTEGO BIOSCIENCES CORPORATION

On April 20, 2007, Tego, a wholly-owned subsidiary of Arrowhead, acquired the assets of C Sixty, Inc., a Texas-based company
developing protective products based on the anti-oxidant properties of fullerenes for $1,000. On July 3, 2007, Arrowhead capitalized Tego with a purchase of 5,000,000 shares of Tego Series A1 Preferred Stock for $100,000. On October 25,
2007, Arrowhead purchased 15,000,000 shares of Tego Series A-2 Preferred Stock for $2.4 million. In line with Tegos revised strategy to focus on the out-license of its technology and to reduce its internal development activities, on
November 21, 2008, Tego repurchased from Arrowhead 5,000,000 shares of Tego Series A-1 Preferred Stock for $1.7 million. Arrowhead owns 100% of the outstanding stock of Tego and 75% on a fully diluted basis. As of March 31, 2010, the
Company has incurred approximately $1,003,000 of expenses related to Tego since its inception.

On December 23, 2009,
Tego completed the sale of all of its non-cash intellectual property assets (Tego IP) to Luna Innovations, Inc. (Luna) under the terms of the Tego-Luna Asset Purchase Agreement dated November 13, 2009 (APA).
The Tego IP includes a portfolio of Tego-owned foreign and domestic patents and patent applications. The Tego IP also includes patent licenses from Siemens AG and Washington University, St. Louis. Under the APA, Luna agreed to assume Tegos
role as licensor under a license Tego granted under the Tego IP to The Bronx Project, Inc. (TBP) to develop carboxyfullerenes in the field of neuronal injury (the TBP License). Luna also assumed Tegos role as licensor
under the exclusive license Tego granted to Arrowheads affiliate Unidym, under the Tego IP in the field of industrial non-pharmaceutical fullerenes.



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Luna paid to Tego an upfront purchase price of $350,000 and reimbursements of patent and
license expenses of $80,000. Further, under the terms of the APA, Luna will pay Tego 10% of any revenues it receives from its licensing or resale of the Tego IP. Tego shall also receive from Luna 50% of any net proceeds Luna receives from the TBP
License. Tego shall receive royalties from Luna for any sales of fullerene products covered by the Tego IP, as well as clinical development milestones totaling $4.25 million for each fullerene product it develops that is covered by the Tego IP.

Due to the sale of substantially all of Tegos assets, the operations of Tego ceased and the gain on the sale and the
results of historical operations are recorded as discontinued operation in the Companys Statements of Operations. Additionally, the cash flows from Tego are reflected separately as cash flows from discontinued operations. Potential future cash
flows associated with the Luna APA, as discussed above, will be reflected as a part of cash flows from discontinued operations in the Companys Consolidated Statement of Cash Flows.

NOTE 5.NOTES PAYABLE

On November 26, 2008, Calando entered into Unsecured Convertible Promissory Note Agreements (Notes) for $2.5 million with
accredited investors and Arrowhead, which invested $200,000 in the Notes offering. Arrowhead subsequently invested an additional $600,000 in the same offering. The Notes mature on November 26, 2010 and bear 10% annual interest. Unpaid principal
of the Notes and accrued but unpaid interest thereon is convertible into common stock of Calando at a conversion price of $0.576647 per share (subject to adjustment) at any time in the sole discretion of the holder. In the event Calando achieves a
liquidation event as defined in the Notes, each note holder has the option to exchange the Notes for two times the then outstanding principal amount owed under the Notes plus accrued and unpaid interest thereon, or convert the outstanding principal
and accrued and unpaid interest thereon into Calando common stock at the conversion price.

Except for one Note in the
principal amount of $500,000, all Notes and accrued interest were converted into a total of 2,950 shares of Calando Series A Preferred Stock on June 23, 2009.

NOTE 6.STOCKHOLDERS EQUITY

At March 31, 2010, the Company had a total of 150,000,000 shares of capital stock authorized for issuance, consisting of 145,000,000
shares of Common Stock, par value $0.001, and 5,000,000 shares of Preferred Stock, par value $0.001.

At March 31, 2010,
63,913,753 shares of Common Stock were outstanding. At March 31, 2010, 1,532,000 shares and 5,003,838 shares were reserved for issuance upon exercise of options granted under Arrowheads 2000 Stock Option Plan and 2004 Equity Incentive
Plan, respectively.

On July 17, 2009 and August 6, 2009, the Company sold an aggregate of 9,196,642 units in a
private placement transaction with institutional and accredited investors. Each unit consisted of one share of Arrowhead Common Stock, $0.001 par value per share, at a price of $0.30 per share, and a warrant to purchase an additional share of Common
Stock exercisable at $0.50 per share. The warrants become exercisable on January 18, 2010 and February 6, 2010, and remain exercisable until June 30, 2014, unless redeemed earlier as permitted. The warrants may be redeemed for nominal
consideration one year and a day after the date of issuance if the Companys Common Stock trades above $1.20 for at least 30 trading days in any 60-day period. Gross proceeds of the offering totaled approximately $2.76 million.

On December 11, 2009, the Company sold an aggregate of 5,083,430 units in a private placement transaction with accredited investors.
Each unit consisted of one share of Arrowhead Common Stock, $0.001 par value per share and a warrant to purchase an additional share of Common Stock exercisable at $0.509 per share. The unit price was $0.634, based upon the closing bid price on the
Companys Common Stock on December 11, 2009 which was $0.509, plus $0.125 for the purchase of the warrant. The warrants become exercisable on June 12, 2010 and remain exercisable until December 11, 2014, unless redeemed earlier
as permitted. The warrants may be redeemed for nominal consideration one year and a day after the date of issuance if the Companys Common Stock trades above $1.20 for at least 30 trading days in any 60-day period. Gross proceeds of the
offering were approximately $3.2 million.

The following table summarizes information about warrants outstanding at
March 31, 2010:



|                           |  |                    |  |                       
|-------------------------- |  | ------------------ |  | ----------------------
|Exercise prices            |  | Number of Warrants |  | RemainingLife in Years
|$5.04                      |  | 1,235,994          |  | 0.8                   
|$7.06                      |  | 948,969            |  | 7.1                   
|$2.00                      |  | 3,863,999          |  | 3.4                   
|$0.50                      |  | 8,531,976          |  | 4.3                   
|$0.51                      |  | 5,083,430          |  | 4.7                   
|                           |  |                    |  |                       
|Total warrants outstanding |  | 19,664,368         |  |                       
|                           |  |                    |  |                       



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NOTE 7.LEASES

As of March 31, 2010, the Company leased the following facilities:



|             |  |                 |  |             |        |                   |                 |            |          
|------------ |  | --------------- |  | ----------- | ------ | ----------------- | --------------- | ---------- | ---------
|             |  | Lab/OfficeSpace |  | MonthlyRent |        | LeaseCommencement |                 | Lease Term
|Arrowhead(1) |  | 7,388 sq ft     |  | $           | 18,101 |                   | March 1, 2006   |            | 62 Months
|Unidym       |  | 20,500 sq ft    |  | $           | 26,650 |                   | October 1, 2008 |            | 60 Months



|(1) | Arrowhead leases corporate office space in Pasadena, which it occupied beginning March 1, 2006. The lease agreement provides Arrowhead with two months free
rent which was recorded as a deferred liability and is being amortized over the life of the lease.
|--- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Facility and
equipment rent expense for the three months ended March 31, 2010 and 2009 was $99,487 and $354,215, respectively. Facility and equipment rent expense for the six months ended March 31, 2010 and 2009 was $253,996 and $682,551, respectively.
From inception to date, rent expense has totaled $4,549,826.

NOTE 8.OBLIGATIONS UNDER CAPITALIZED LEASE

As part of the purchase of Nanoconduction, the Company assumed a capitalized lease for equipment valued at $1,677,000. Research and
development equipment under capitalized lease was allocated a cost of $0 at the Nanoconduction acquisition by Unidym as the equipment has no alternative use.

At March 31, 2010, the future minimum commitments remaining under capitalized leases are as follows:



|                                                                                                                     |  |   |         |  
|-------------------------------------------------------------------------------------------------------------------- |  | - | ------- | -
|Capitalized lease payable in four monthly installments of $75,343, due in July 2010, secured by equipment at
Unidym. |  | $ | 301,376 |  
|                                                                                                                     |  |   |         |  
|Less interest                                                                                                        |  |   | (4,957  | )
|                                                                                                                     |  |   |         |  
|Present value of future minimum payments                                                                             |  |   | 296,419 |  
|Less current portion                                                                                                 |  |   | 296,419 |  
|                                                                                                                     |  |   |         |  
|Long term portion                                                                                                    |  | $ |        |  
|                                                                                                                     |  |   |         |  

NOTE 9.STOCK BASED COMPENSATION

Arrowhead has two plans that provide for equity-based compensation. Under the 2000 Stock Option Plan, 1,532,000 shares of Arrowheads
Common Stock are reserved for issuance upon exercise of non-qualified stock options. No further grants can be made under the 2000 Stock Option Plan. The 2004 Equity Incentive Plan reserves 5,738,310 shares for the grant of stock options, stock
appreciation rights, restricted stock awards and performance unit/share awards by the Board of Directors to employees, consultants and others. As of March 31, 2010, there were options granted and outstanding to purchase 1,532,000 and 5,003,838
shares of Common Stock under the 2000 Stock Option Plan and the 2004 Equity Incentive Plan, respectively. During the quarter ended March 31, 2010, 1,384,250 options were granted under the 2004 Equity Incentive Plan.

In connection with a private offering in fiscal 2009, directors, officers and employees of the Company agreed to terminate options to
purchase 4,005,000 shares of Common Stock with exercise prices ranging from $2.52 to $6.83. In consideration of the termination of the option agreements, other existing grants to purchase 450,000 shares were accelerated such that the awards are
fully vested on the one year anniversary of the date of grant. The cancellation was effective July 17, 2009.



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The following tables summarize information about stock options:



|                              |  |                             |   |  |                                        |      |                                          |           |                         |   |          
|----------------------------- |  | --------------------------- | - |  | -------------------------------------- | ---- | ---------------------------------------- | --------- | ----------------------- | - | ---------
|                              |  | Number ofOptionsOutstanding |   |  | Weighted-AverageExercisePricePer Share |      | Weighted-AverageRemainingContractualTerm |           | AggregateIntrinsicValue
|Balance At September 30, 2008 |  | 8,007,632                   |   |  | $                                      | 3.24 |                                          |           |                         |   |          
|Granted                       |  | 460,000                     |   |  |                                        | 0.85 |                                          |           |                         |   |          
|Canceled                      |  | (5,566,044                  | ) |  |                                        | 3.88 |                                          |           |                         |   |          
|Exercised                     |  |                            |   |  |                                        |     |                                          |           |                         |   |          
|                              |  |                             |   |  |                                        |      |                                          |           |                         |   |          
|Balance At September 30, 2009 |  | 2,901,588                   |   |  |                                        | 1.73 |                                          |           |                         |   |          
|Granted                       |  | 2,250,000                   |   |  |                                        | 0.53 |                                          |           |                         |   |          
|Canceled                      |  |                            |   |  |                                        |     |                                          |           |                         |   |          
|Exercised                     |  |                            |   |  |                                        |     |                                          |           |                         |   |          
|                              |  |                             |   |  |                                        |      |                                          |           |                         |   |          
|Balance At December 31, 2009  |  | 5,151,588                   |   |  | $                                      | 1.21 |                                          | 7.7 years |                         | $ | 45,595   
|Granted                       |  | 1,384,250                   |   |  |                                        | 0.52 |                                          |           |                         |   |          
|Canceled                      |  |                            |   |  |                                        |     |                                          |           |                         |   |          
|Exercised                     |  |                            |   |  |                                        |     |                                          |           |                         |   |          
|                              |  |                             |   |  |                                        |      |                                          |           |                         |   |          
|Balance At March 31, 2010     |  | 6,535,838                   |   |  | $                                      | 1.06 |                                          | 8.0 years |                         | $ | 2,519,865
|                              |  |                             |   |  |                                        |      |                                          |           |                         |   |          
|Exercisable At March 31, 2010 |  | 3,110,097                   |   |  | $                                      | 1.50 |                                          | 7.1 years |                         | $ | 549,444  

Stock-based
compensation expense for the six months ended March 31, 2010 and 2009 was $598,230 and $1,423,209, respectively, and is included in salary expense in the Companys consolidated statements of operations. There is no income tax benefit as
the company is currently operating at a loss and an actual income tax benefit may not be realized. The result of the loss creates a timing difference, resulting in a deferred tax asset, which is fully reserved by a valuation allowance.

At March 31, 2010, there were 734,472 options available for future grants under Arrowheads 2004 Equity Incentive Plan.

The fair value of the options granted by Arrowhead for the six months ended March 31, 2010 and 2009 is estimated at
$1,584,000 and $230,000, respectively.

As of March 31, 2010, the pre-tax compensation expense for all unvested stock
options at Arrowhead in the amount of approximately $1,770,965 will be recognized in our results of operations over a weighted average period of 2.0 years. As of March 31, 2010, the pre-tax compensation expense for all unvested stock options at
Unidym and Calando in the amount of approximately $700,825 will be recognized in our results of operations over a weighted average period of 2.7 and 1.9 years, respectively.

No options were granted by Calando and Tego during the three months ended March 31, 2010 and 2009. During the three months ended
March 31, 2010 and 2009, Unidym issued 100,000 and 0 options, respectively.

The fair value of options is estimated at
the date of grant using the Black-Scholes option-pricing model with the following weighted-average assumptions: dividend yield of 0%, expected volatility of 49% to 100% (0% to 81% for Subsidiaries), risk-free interest rate of 2.34% to 5.10% and
expected life of five to six years. The weighted-average fair value of options granted by Arrowhead for the six months ended March 31, 2010 and 2009 is estimated at $0.39 and $0.64, respectively.

The Black-Scholes option valuation model was developed for use in estimating the fair value of traded options, which do not have vesting
restrictions and are fully transferable. In addition, option valuation models require the input of highly subjective assumptions, including the expected stock price volatility. Because the Companys employee stock options have characteristics
significantly different from those of traded options, and because changes in the subjective input assumptions can materially affect the fair value estimate, in managements opinion, the existing models do not necessarily provide a reliable
single measure of the fair value of its employee stock options.

NOTE 10.FAIR VALUE MEASUREMENTS & DERIVATIVE
INSTRUMENTS

The Company measures its financial assets and liabilities at fair value. Fair value is defined as the
price that would be received to sell an asset or paid to transfer a liability (i.e., exit price) in an orderly transaction between market participants at the measurement date. Additionally, the Company is required to provide disclosure and
categorize assets and liabilities measured at fair value into one of three different levels depending on the assumptions (i.e., inputs) used in the valuation. Level 1 provides the most reliable measure of fair value while Level 3 generally
requires significant management judgment. Financial assets and liabilities are classified in their entirety based on the lowest level of input significant to the fair value measurement. The fair value hierarchy is defined as follows:

Level 1Valuations are based on unadjusted quoted prices in active markets for identical assets or liabilities.



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Level 2Valuations are based on quoted prices for similar assets or liabilities in
active markets, or quoted prices in markets that are not active for which significant inputs are observable, either directly or indirectly.

Level 3Valuations are based on prices or valuation techniques that require inputs that are both unobservable and significant
to the overall fair value measurement. Inputs reflect managements best estimate of what market participants would use in valuing the asset or liability at the measurement date.

The following table summarizes fair value measurements at March 31, 2010 for assets and liabilities measured at fair value on a
recurring basis:



|                          |  |         |           |          |   |           |  |       |   |  |   |          
|------------------------- |  | ------- | --------- | -------- | - | --------- |  | ----- | - |  | - | ---------
|                          |  | Level I |           | Level II |   | Level III |  | Total
|Cash and cash equivalents |  | $       | 2,593,044 |          | $ |          |  | $     |  |  | $ | 2,593,044
|Derivative liabilities    |  | $       |          |          | $ |          |  | $     |  |  | $ |         

During 2009,
Arrowheads subsidiary, Unidym, issued Series D Preferred Stock. The rights of the Preferred Stock necessitate the presentation of the fair value of the conversion feature as a liability. These rights include those that protect the holders from
decline in the Companys stock price, which is considered outside the control of the Company. The derivative liabilities are marked-to-market each reporting period and changes in fair value are recorded as a non-operating gain or loss in the
statement of operations, until they are completely settled. The fair value of the conversion feature is determined each reporting period using the Black-Scholes option pricing model, and is affected by changes in inputs to that model including our
stock price, expected stock price volatility, interest rates and expected term. The assumptions used in valuing the derivative liability at March 31, 2010 were as follows:



|                        |  |         |  
|----------------------- |  | ------- | -
|Risk free interest rate |  | 1       | %
|Expected life           |  | 3 Years |  
|Dividend yield          |  | none    |  
|Volatility              |  | 30      | %

The following is a
reconciliation of the derivative liability for the six months ended March 31, 2010:



|                            |  |   |  
|--------------------------- |  | - | -
|Value at October 1, 2009    |  | $ | 0
|Modification of instruments |  |   | 
|Decrease in value           |  |   | 
|                            |  |   |  
|Value at March 31, 2010     |  | $ | 0
|                            |  |   |  

The carrying amounts of the Companys other
financial instruments, which include accounts receivable and accounts payable, approximate their respective fair values due to the relatively short-term nature of these instruments. Based upon interest rates currently available to the Company for
debt with similar terms, the carrying value of the Companys long-term debt is approximately equal to its fair value.

NOTE 11.RELATED PARTY TRANSACTIONS

During the six months ended March 31, 2010, the Companys
majority-owned subsidiary, Unidym, had product sales of $0 to one of its stockholders, Sumitomo Corporation (Sumitomo). During the three and six months ended March 31, 2009, sales to Sumitomo were $15,500 and $47,218, respectively.
On July 31, 2009, Unidym terminated its contract with Sumitomo as its major product distributor in Japan.

During the six
months ended March 31, 2010 and 2009, the Companys majority-owned subsidiary, Calando, paid $0 and $40,000, respectively, in consulting fees to Dr. Mark Davis of the California Institute of Technology (Caltech), a former
director and consultant of Calando.

Through the Benet Group, Dr. Anzalone owns 1,395,900 shares of Nanotope common stock
or approximately 14.2% of Nanotopes outstanding voting securities. Dr. Anzalone does not hold options, warrants or any other rights to acquire securities of Nanotope directly or through the Benet Group. The Benet Group has the right to
appoint a representative to the board of directors of Nanotope. Dr. Anzalone currently serves on the Nanotope board in a seat reserved for Nanotopes CEO, and another individual holds the seat designated by the Benet Group.
Dr. Anzalone has served as President and Chief Executive Officer of Nanotope since its formation and continues to serve in these capacities. Dr. Anzalone has not received any compensation for his work on behalf of Nanotope since joining
the Company on December 1, 2007. Dr. Anzalone has also waived his right to any unpaid compensation accrued for work done on behalf of Nanotope before he joined the Company.



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Dr. Anzalone did not participate on behalf of the Company in the negotiations of the
terms of the Nanotope Series B Preferred Stock issued to the Company and did not negotiate on behalf of Nanotope after becoming the Chief Executive Officer and President of the Company. Dr. Anzalone did respond to questions asked of him by the
Companys Board of Directors and management regarding Nanotopes business plan, operations and the terms of the Series B Stock Purchase Agreement and ancillary agreements.

During the year ended September 30, 2009, Calando raised $2.5 million through the sale of senior unsecured convertible promissory
notes (New Notes), to accredited investors, plus $800,000 from Arrowhead. Dr. Anzalone, Arrowheads President and CEO, personally participated in the offering by buying $100,000 of the New Notes.

As part of the private placement on December 11, 2009 (see Note 6. Stockholders Equity), Dr. Anzalone, Arrowheads
President and CEO, personally invested $100,000.

NOTE 12.SUBSEQUENT EVENTS

On April 14, 2010, the Company received a notification from the NASDAQ Stock Market indicating that the Company has regained
compliance with NASDAQ Rule 5550(a)(2) in that the Companys closing bid price has been at $1.00 per share or greater for at least ten consecutive business days. The April 14, 2010 notification also stated that the matter of the
deficiency, as set forth in the previously reported September 15, 2009 deficiency notice, is now closed.



|ITEM 2. | MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.
|------- | --------------------------------------------------------------------------------------

This Quarterly Report on Form 10-Q contains certain forward-looking statements within the meaning of Section 27A of the Securities
Act of 1933 and Section 21E of the Securities Exchange Act of 1934, and we intend that such forward-looking statements be subject to the safe harbors created thereby. For this purpose, any statements contained in this Quarterly Report on Form
10-Q except for historical information may be deemed to be forward-looking statements. Without limiting the generality of the foregoing, words such as may, will, expect, believe,
anticipate, intend, could, estimate, or continue or the negative or other variations thereof or comparable terminology are intended to identify forward-looking statements. In addition, any
statements that refer to projections of our future financial performance, trends in our businesses, or other characterizations of future events or circumstances are forward-looking statements.

The forward-looking statements included herein are based on current expectations of our management based on available information and
involve a number of risks and uncertainties, all of which are difficult or impossible to predict accurately and many of which are beyond our control. As such, our actual results may differ significantly from those expressed in any forward-looking
statements. Readers should carefully review the factors identified in this report under the caption Risk Factors as well as the additional risks described in other documents we file from time to time with the Securities and Exchange
Commission (SEC), including our most recent Annual Report on Form 10-K. In light of the significant risks and uncertainties inherent in the forward-looking information included herein, the inclusion of such information should not be
regarded as a representation by us or any other person that such results will be achieved, and readers are cautioned not to place undue reliance on such forward-looking information. Except as may be required by law, disclaim any intent to revise the
forward-looking statements contained herein to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.

Overview

Arrowhead Research Corporation is a development stage nanotechnology holding company that forms, acquires, and operates subsidiaries
commercializing innovative nanotechnologies. By working closely with leading scientists and universities, the Company identifies advances in nanotechnology and matches them with product development opportunities in high-growth markets. The Company
is currently focused on the electronics and biotech industries.

By providing strategic management, financing, and operational
services to its subsidiaries, Arrowhead takes an active role in their development, allowing the business and technical development teams at the subsidiary companies to remain focused on near term revenue opportunities and capital efficiency.
Arrowheads ultimate goal is to monetize the value of its subsidiaries through an initial public offering of subsidiary stock or a sale of a subsidiary to another company. Alternatively, Arrowhead could retain ownership of its subsidiary to
capture its continuing cash flow and income.

Arrowheads portfolio includes two majority-owned Subsidiaries, Unidym and
Calando, and minority investments in two early-stage nanotechnology companies, Nanotope and Leonardo. Arrowheads business plan includes adding to its portfolio through selective acquisition and formation of new companies, as capital resources
allow. The Companys Subsidiaries are seeking to commercialize or license the technology covering a variety of nanotechnology products and applications, including anti-cancer RNAi therapeutics and carbon-based electronics. The Companys
minority investments are focused on developing advanced nanomaterials for spinal cord injury and wound healing and drug delivery technology.



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Arrowhead has been active in the operation of its subsidiaries, providing key management
functions. During 2009, the Company continued its efforts to streamline the operations of Arrowhead and its Subsidiaries to increase efficiency and decrease costs while continuing to move the business plans of each entity forward. With the decision
to move to a licensing model for Calando and the decision to reduce costs at Unidym, the amount of cash needed to fund both operations has been substantially reduced from historical levels.

Liquidity and Capital Resources

At March 31, 2010, the Company had approximately $2.6 million in cash to fund operations. Arrowhead has historically financed its
operations through the sale of securities of Arrowhead and its Subsidiaries. During fiscal 2009, the Company obtained $7.3 million in cash through equity and debt financing, including $2.5 million raised by Calando through the sale of senior
unsecured convertible promissory notes, and $2.0 million raised by Unidym through the sale of newly issued shares of Series C-1 Preferred Stock. Also during fiscal 2009, the Company obtained an additional $4.4 million from the sales of assets,
products and license fees, including the sale by Unidym of its equity interest in Ensysce BioSciences Inc. for $700,000. During the first half of fiscal 2010, the Company received $3.5 million in cash through an equity financing, $0.5 million from
the exercise of warrants, and $0.7 million from revenue and asset sales, including the sale of the Tego IP. The company anticipates that further equity financings, and/or asset sales and license agreements will be necessary to continue to fund
operations.

Since inception in May 2003, the Company has incurred significant losses. Cash and cash equivalents increased
during the first half of fiscal 2010 by $0.6 million to $2.6 million at March 31, 2010 from $2.0 million at September 30, 2009. The increase in cash was mainly due to proceeds from the issuance of Common Stock of $4.0 million, proceeds
from the disposal of Tego of $0.4 million, cash collections from revenue of $0.3 million, offset by cash operating expenses of approximately $3.7 million and cash payments on capital leases of $0.4 million. The Company invests available cash in
certificates of deposit, U.S. government obligations and high grade commercial paper. The Companys investment objectives are primarily to preserve capital and liquidity and secondarily to obtain investment income.

The Companys strategic plan includes focusing on near term revenue opportunities, conserving cash and seeking sources of new
capital. To execute this plan, the Company will seek to accomplish one or more of the following on favorable terms: the out-license of technology, sale of a subsidiary, sale of non-core assets, scaling down development efforts, funded joint
development or partnership arrangements and sale of securities. The likelihood that any of these events will occur is uncertain, especially in light of the lack of liquidity in the current capital and credit markets. Until such time as one or more
of these goals is accomplished, the Company has scaled back the activities at its Subsidiaries.

Majority-owned Subsidiaries

Unidym

Unidym is a leader in the commercialization of carbon nanotube-based transparent, conductive films (TCFs) for the electronics industry.
TCFs are a critical component in devices such as touch panels, displays and thin-film solar cells. For example, both touch panels and LCDs typically employ two TCF layers per device. Unidyms TCFs offer substantial advantages over the incumbent
technology, indium-based metal oxides, including improved durability, lower processing costs, and lower overall cost structure. Unidym is working in close collaboration with customers, particularly in Asia where most of display manufacturing is
located. Unidym is initially focused on the touch panel market and expects modest revenue from sales of its films in the near term. During the first half of fiscal 2010, Unidym continued business and technical development for its films. Two of its
joint development agreements with Samsung Electronics, Co., Ltd. were extended, and Unidym entered into an agreement to form a joint venture in Korea to market and co-develop film and electronic ink products for the Korean touch panel and display
industries.

The development, production and sale of Unidyms products have required, and are expected to continue to
require significant investment and time. There are a variety of technical, cost and marketing barriers that must be overcome. It is not possible at this time to predict the final cost of developing Unidyms transparent conductive film or other
CNT products, the final cost of scaling up the production process, when or if Unidym will generate significant licensing revenue or when or if Unidym will become profitable. At March 31, 2010, Arrowheads ownership interest in Unidym was
80% and 63% on a fully diluted basis.

Calando

Calando is a clinical stage oncology drug delivery company. Calando has developed proprietary technologies to create
targeted siRNA-based therapeutics. Calandos innovative RONDEL nanoparticle system has been designed to
solve the long-standing obstacle of safe and effective delivery and targeting for siRNA therapeutics. Calandos initial focus has been on the treatment of cancer. Calandos clinical stage drug candidate, CALAA-001, based on siRNA and the
RONDEL system, is currently undergoing a Phase I clinical study. The trial is utilizing a dose escalation
protocol, which is nearing the highest dose in the protocol and yielding recent promising results with no serious side effects. Calando plans to complete the Phase I trial, as capital resources allow, and is seeking a partner for the further
development of both the siRNA delivery platform and CALAA-01.



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In March 2010, results were published from a study using samples from a
Phase I clinical trial, conducted by Calando, which demonstrated systemic delivery of siRNA and the successful silencing of a widely recognized cancer gene via RNA interference in humans. This represents a breakthrough for Calando, as
well as its proprietary RONDEL delivery system, and holds the potential to be a significant development in the
field of RNAi therapies.

In June 2009, after completion of a Phase 1 clinical trial with a positive safety profile and
indications of efficacy, Cyclosert and its associated clinical candidate, IT-101, were licensed for further development to Cerulean Pharma, Inc., a Boston, Massachusetts based biotech company. Under the terms of the agreements, Cerulean will pay
Calando future potential partnering, milestone and royalty payments as the development of Cyclosert and IT-101 progresses.

We
believe there is an opportunity to derive value from the further development of the Calando platform drug delivery systems, as they have been demonstrated to enhance and enable the delivery of diverse pharmaceutical entities, including peptides and
small molecules as well as other RNA and DNA-based oligonucleotides. At March 31, 2010, Arrowheads ownership interest in Calando was 70% and 62% on a fully diluted basis.

The development of CALAA-01, IT-101 and other pipeline candidates are preliminary, and there is no assurance that they will be
successful. There are numerous technical, regulatory and marketing challenges that must be overcome to successfully commercialize Calandos products, including, but not limited to the following:



| |  |  | Advancing pipeline candidates require extensive preclinical testing and approval by the U.S. Food and Drug Administration (FDA) before
clinical testing can commence.
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | Advancing therapeutic candidates through preclinical and clinical testing is expensive, resource intensive and time consuming.
| | - |  | ------------------------------------------------------------------------------------------------------------------------------



| |  |  | Complications may arise that would cause the clinical testing to be interrupted or stopped. FDA approval is required before products can be sold.
| | - |  | -------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | Even if FDA approval is eventually obtained, there is no assurance that it will be accepted by the medical community.
| | - |  | ---------------------------------------------------------------------------------------------------------------------

It is not possible at this time to accurately determine the final cost of the development projects, the completion dates, or when or if
revenue will commence.

Wholly-owned Subsidiaries

Tego

Tego had
been pursuing a licensing and partnering strategy. In line with this strategy, on July 1, 2009, Tego exclusively licensed to The Bronx Project, Inc. (TBP), a development stage pharmaceutical company, the rights to develop and
commercialize carboxylated fullerenes, e.g., the fullerene C3, in the fields of Parkinsons disease, amyotrophic lateral sclerosis (or Lou Gehrigs disease), multiple sclerosis, brain trauma and schizophrenia. The
TBP License provided Tego with $100,000 in upfront fees, $2.35 million in potential milestone payments and royalties, as well as 5% of the proceeds of a sale of TBP itself to a third party.

Further, on December 23, 2009, Tego completed the sale of all of its non-cash intellectual property assets (Tego IP) to
Luna Innovations, Inc. (Luna) under the terms of the Tego-Luna Asset Purchase Agreement dated November 13, 2009 (APA). The Tego IP includes a portfolio of Tego-owned foreign and domestic patents and patent applications.
The Tego IP also includes patent licenses from Siemens AG and Washington University, St. Louis. Under the APA, Luna agreed to assume Tegos role as licensor under a license Tego granted under the Tego IP to The Bronx Project, Inc. Luna also
assumed Tegos role as licensor under the exclusive license Tego granted to Arrowheads affiliate Unidym, under the Tego IP in the field of industrial non-pharmaceutical fullerenes.

As a result of the sale to Luna, the operations of Tego ceased and the gain on the sale and the results of historical operations are
recorded as discontinued operation in the Companys Statements of Operations. Additionally, the cash flows from Tego are reflected separately as cash flows from discontinued operations. Potential future cash flows associated with the Luna APA
will be reflected as a part of cash flows from discontinued operations in the Companys Consolidated Statement of Cash Flows.

Agonn

As part of
Arrowheads strategy to conserve cash, Agonn ceased its development efforts.



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Minority Investments

Nanotope, Inc.

Nanotope is an early stage nano-biotechnology company developing advanced materials for regeneration and wound healing. Arrowhead has a
23% ownership interest in Nanotope and accounts for its investment in Nanotope using the equity method of accounting. Nanotope is positioned to enter into a commercialization corporate partnership in 2010 and expects to be able to start a first
round of clinical trials in 2010. Nanotopes model is to partner product candidates prior to clinical trials and, therefore, assume no clinical costs.

Leonardo Biosystems, Inc.

Leonardo is a drug delivery company based on technology developed by Dr. Mauro Ferrari, one of the worlds best-known
nano-cancer scientists. Leonardos research is focused on developing an advanced set of nanotechnology tools to deliver anti-cancer therapeutics. Arrowhead has a 5% ownership interest in Leonardo and accounts for its investment using the cost
method of accounting.

Factors Affecting Further R&D Expenses

Since early fiscal 2009, the Company has dramatically decreased its research and development expenses due to cash constraints. Research
and development expenses are expected to fluctuate in the foreseeable future as the Companys product development efforts move through various phases of development and as capital resources allow. Each phase of development requires different
resources. Also, the pace of development can affect the resources required. Over the past five years, the Company has increased and decreased subsidiaries and products in its pipeline, increased and decreased research and development personnel,
engineers, business development and marketing personnel; expanded and contracted its pre-clinical research, begun and ended clinical trial activities, increased its regulatory compliance capabilities, and purchased capital equipment and laboratory
supplies. The timing and amount of these fluctuations in expenses is difficult to predict due to the uncertainty inherent in the timing and extent of progress in the Companys research programs. As the Companys research efforts evolve, it
will continue to review the direction of its research based on an assessment of the value of possible commercial applications emerging from these efforts.

In addition to these general factors, specific factors that will determine the eventual cost to complete the current projects at
Arrowheads nano-biotechnology Subsidiaries or their partners and potential partners include the following:



| |  |  | the number, size and duration of clinical trials required to gain FDA approval;
| | - |  | -------------------------------------------------------------------------------



| |  |  | the costs of producing supplies of the drug candidates needed for clinical trials and regulatory submissions;
| | - |  | -------------------------------------------------------------------------------------------------------------



| |  |  | the efficacy and safety profile of the drug candidate; and
| | - |  | ----------------------------------------------------------



| |  |  | the costs and timing of, and the ability to secure, regulatory approvals.
| | - |  | -------------------------------------------------------------------------

It is possible that the completion of studies could be delayed for a variety of reasons, including difficulties in enrolling patients,
delays in manufacturing, incomplete or inconsistent data from the pre-clinical or clinical trials, difficulties evaluating the trial results and lack of funding. Any delay in completion of a trial would increase the cost of that trial. Due to these
uncertainties, the Company cannot reasonably estimate the amount or timing of cash inflows from Calandos current activities.

Critical Accounting Policies and Estimates

Management makes certain judgments and uses certain estimates and assumptions when applying accounting principles generally accepted in
the United States in the preparation of our Consolidated Financial Statements. We evaluate our estimates and judgments on an ongoing basis and base our estimates on historical experience and on assumptions that we believe to be reasonable under the
circumstances. Our experience and assumptions form the basis for our judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may vary from what we anticipate and different
assumptions or estimates about the future could change our reported results. We believe the following accounting policies are the most critical to us, in that they are important to the portrayal of our consolidated financial statements and require
our most difficult, subjective or complex judgments in the preparation of our consolidated financial statements. For further information, see Note 1, Organization and Significant Accounting Policies, to our Consolidated Financial Statements
which outlines our application of significant accounting policies and new accounting standards.

Revenue Recognition

Revenue from product sales are recorded when persuasive evidence of an arrangement exists, title has passed and delivery has
occurred, a price is fixed and determinable, and collection is reasonably assured.



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We may generate revenue from product sales, technology licenses, collaborative research and
development arrangements, and research grants. Revenue under technology licenses and collaborative agreements typically consists of nonrefundable and/or guaranteed technology license fees, collaborative research funding, and various milestone and
future product royalty or profit-sharing payments.

Revenue associated with research and development funding payments under
collaborative agreements is recognized ratably over the relevant periods specified in the agreement, generally the research and development period. Revenue from up-front license fees, milestones and product royalties are recognized as earned based
on the completion of the milestones and product sales, as defined in the respective agreements. Payments received in advance of recognition as revenue are recorded as deferred revenue.

Research and Development Expenses

Research and development expenses include salaries and benefits, trial (including pre-clinical, clinical and other) and production costs,
purchased in-process research expenses, contract and other outside service fees, and facilities and overhead costs related to research and development efforts. Research and development expenses also consist of costs incurred for proprietary and
collaborative research and development. Research and development costs are expensed as incurred.

Impairment of Long-lived
Assets

We review long-lived assets for impairment whenever events or changes in business circumstances indicate that the
carrying amount of assets may not be fully recoverable or that our assumptions about the useful lives of these assets are no longer appropriate. If impairment is indicated, the asset is written down to its estimated fair value.

Intellectual Property

Intellectual property consists of patents and patent applications internally developed, licensed from universities or other third parties
or obtained through acquisition. Patents and patent applications are reviewed for impairment whenever events or circumstances indicate that the carrying amount may not be recoverable, and appropriate adjustments recorded. Purchased or licensed
patents are amortized over the remaining life of the patent, generally three to twenty years.

Recent Accounting
Pronouncements

See Note 1 to the consolidated financial statements for information concerning the Companys
implementation and impact of new accounting guidance.

Results of Operations

The Company had a consolidated loss attributable to Arrowhead of approximately $1.9 million for the three months ended March 31,
2010, compared to a consolidated loss attributable to Arrowhead of $5.3 million for the three months ended March 31, 2009.

The decrease in the fiscal 2010 quarterly loss over fiscal 2009 quarterly loss is the result of several factors. The number of management
and staff employees at Arrowhead declined over fiscal 2009 and other cost savings measures were instituted, including the closure of Arrowheads New York office and reduction in scientific advisory fees.

Unidym also reduced its expenses in fiscal 2009 and maintained a reduced level of costs into fiscal 2010. In fiscal 2008, Unidym was
pursuing a business plan based on building a vertically integrated company that would manufacture both carbon nanotubes and carbon nanotube films. With the dramatic changes in economic conditions in late 2008, Unidym decided to look to partners for
manufacturing capability rather than expand its internal capabilities. In line with this strategy, Unidym closed its Texas operations in January 2009. This resulted in a reduction in workforce and other expenses related to the operation of the Texas
plant and a reduction in lease expenses later in the year. Unidym consolidated its Northern California operations into one facility in 2009 and also decreased the number of management and technical staff in the early part of the year. Significant
expense is expected to be incurred in the further development of Unidyms products. However, development costs at Unidym have been substantially reduced and the pace of development will depend on the cash resources and partnership opportunities
available to Unidym.

Calando also reduced expenses in fiscal 2009 due to a change in business strategy. Rather than bear the
significant expense of running multiple clinical trials, Calando decided to seek partners for further development of its technology. Beginning in fiscal 2008 and continuing into fiscal 2009, Calando reduced its management and technical staff
culminating with the closure of its lab facility in Pasadena, California in June 2009 after a partnership for one of its drug delivery technologies and its associated clinical candidate was signed. In fiscal 2009, significant expense was incurred
for manufacture of the components for CALAA-02, preparation for an investigational new drug (IND) application for CALAA-02 and the continuation of Calandos clinical trials. Continued clinical and preclinical development of
Calandos drug candidates will depend on the cash resources available to Calando.



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During the quarter ended March 31, 2010, the Company experienced similar operating
losses and cash burn as compared to the quarter ended December 31, 2009. The Company has completed its cost reduction programs, and does not expect further reductions in it operating expenses or cash burn.

Revenues

The Company
generated revenues of $157,346, and $235,650 during the three months ended March 31, 2010 and 2009, respectively. Revenue for the three months ended March 31, 2010 consists primarily of Unidym sales of CNTs and inks; and revenue for the
three months ended March 31, 2009 primarily consisted of Unidym grant revenue of $118,000, and $88,000 from the sales and delivery of carbon nanotubes by Unidym. Revenues from sales of carbon nanotubes are expected to decline in fiscal 2010 as
Unidym depletes its inventories and transfers its bulk carbon nanotube production to a third party in exchange for payments based on the third party sales. Unidym is anticipating modest revenue from film sales in fiscal 2010.

Operating Expenses

The
analysis below details the operating expenses and discusses the expenditures of the Company within the major expense categories. The following tables provide details of operating expenses for the three and six months ended March 31, 2010 and
2009.

Salary & Wage Expenses  Three and six months ended March 31, 2010 compared to the three and six months ended
March 31, 2009

Arrowhead employs management, administrative and technical staff at the Arrowhead corporate
offices and the Subsidiaries. Salary and wage expense consists of salary, benefits, and non-cash charges related to equity-based compensation in the form of stock options. Salary and benefits are allocated to two major categories: general and
administrative (G&A) compensation related expense and research and development (R&D) compensation related expense depending on the primary activities of each employee. The following tables provide detail of salary and
wage expenses for the three and six months ended March 31, 2010 as compared to the three and six months ended March 31, 2009.

(in thousands)



|                           |  |                                  |       |                     |     |                     |                                 |   |                     |  |     |   |  |   |        |   |  |     |  
|-------------------------- |  | -------------------------------- | ----- | ------------------- | --- | ------------------- | ------------------------------- | - | ------------------- |  | --- | - |  | - | ------ | - |  | --- | -
|                           |  | Three 
MonthsEndedMarch 31, 2010 |       | % ofExpenseCategory |     |                     | Three
MonthsEndedMarch 31, 2009 |   | % ofExpenseCategory |  |     |   |  |   |        |  
|                           |  |                                  |       |                     |     | Increase (Decrease) |                                
|                           |  |                                  |       |                     |     | $                   |                                 |   | %                   | 
|G&A - compensation-related |  | $                                | 463   |                     | 45  | %                   |                                 | $ | 1,061               |  | 44  | % |  | $ | (598   | ) |  | -56 | %
|Stock-based compensation   |  |                                  | 296   |                     | 28  | %                   |                                 |   | 696                 |  | 28  | % |  |   | (400   | ) |  | -57 | %
|R&D - compensation-related |  |                                  | 286   |                     | 27  | %                   |                                 |   | 677                 |  | 28  | % |  |   | (391   | ) |  | -58 | %
|                           |  |                                  |       |                     |     |                     |                                 |   |                     |  |     |   |  |   |        |   |  |     |  
|Total                      |  | $                                | 1,045 |                     | 100 | %                   |                                 | $ | 2,434               |  | 100 | % |  | $ | (1,389 | ) |  | -57 | %
|                           |  |                                  |       |                     |     |                     |                                 |   |                     |  |     |   |  |   |        |   |  |     |  

(in thousands)



|                           |  |                               |       |                     |     |                     |                               |   |                     |  |     |   |  |   |        |   |  |     |  
|-------------------------- |  | ----------------------------- | ----- | ------------------- | --- | ------------------- | ----------------------------- | - | ------------------- |  | --- | - |  | - | ------ | - |  | --- | -
|                           |  | Six
MonthsEndedMarch 31, 2010 |       | % ofExpenseCategory |     |                     | Six
MonthsEndedMarch 31, 2009 |   | % ofExpenseCategory |  |     |   |  |   |        |  
|                           |  |                               |       |                     |     | Increase (Decrease) |                              
|                           |  |                               |       |                     |     | $                   |                               |   | %                   | 
|G&A - compensation-related |  | $                             | 1,018 |                     | 47  | %                   |                               | $ | 2,368               |  | 43  | % |  | $ | (1,350 | ) |  | -57 | %
|Stock-based compensation   |  |                               | 598   |                     | 28  | %                   |                               |   | 1,423               |  | 25  | % |  |   | (825   | ) |  | -58 | %
|R&D - compensation-related |  |                               | 533   |                     | 25  | %                   |                               |   | 1,770               |  | 32  | % |  |   | (1,237 | ) |  | -70 | %
|                           |  |                               |       |                     |     |                     |                               |   |                     |  |     |   |  |   |        |   |  |     |  
|Total                      |  | $                             | 2,149 |                     | 100 | %                   |                               | $ | 5,561               |  | 100 | % |  | $ | (3,412 | ) |  | -61 | %
|                           |  |                               |       |                     |     |                     |                               |   |                     |  |     |   |  |   |        |   |  |     |  

During the three and six months ended March 31, 2010, G&A compensation expense decreased due to a
reduction in the number of employees across all entities during fiscal 2009.

Stock-based compensation is a non-cash charge
related to the issuance and vesting of stock options. This expensing of stock-based compensation is based upon the estimated fair value of the awards issued. During fiscal 2009, the Company cancelled options to purchase approximately
5.6 million shares due to employee terminations and voluntary terminations of stock options to facilitate financing transactions in July and August 2009. These cancellations resulted in lower stock-based compensation expense during the three
and six months ended March 31, 2010, as compared to the three and six months ended March 31, 2009. The number of options outstanding and the option expense will vary from period to period depending on hiring, terminations and awards to new
and existing employees.



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R&D compensation expense decreased significantly during the three and six months ended
March 31, 2010, as compared to the three and six months ended March 31, 2009. This reduction is primarily due to Unidyms reduction in research scientists and process engineers in conjunction with the closure of Unidyms Texas
facility. Calando has also reduced laboratory personnel in connection with its decision in June 2009 to license its technology and close its laboratory facility. Two employees have been retained to complete the CALAA-01 clinical study and to
facilitate partnership arrangements for Calandos technology.

General & Administrative Expenses  Three and six
months ended March 31, 2010 compared to the three and six months ended March 31, 2009

The following tables
provide detail of G&A expenses for the three and six months ended March 31, 2010 as compared to the three and six months ended March 31, 2009.

(in thousands)



|                              |  |                                 |     |                     |     |                     |                                 |   |                     |  |     |   |  |   |      |   |  |      |  
|----------------------------- |  | ------------------------------- | --- | ------------------- | --- | ------------------- | ------------------------------- | - | ------------------- |  | --- | - |  | - | ---- | - |  | ---- | -
|                              |  | Three
MonthsEndedMarch 31, 2010 |     | % ofExpenseCategory |     |                     | Three
MonthsEndedMarch 31, 2009 |   | % ofExpenseCategory |  |     |   |  |   |      |  
|                              |  |                                 |     |                     |     | Increase (Decrease) |                                
|                              |  |                                 |     |                     |     | $                   |                                 |   | %                   | 
|Professional/outside services |  | $                               | 303 |                     | 41  | %                   |                                 | $ | 540                 |  | 52  | % |  | $ | (237 | ) |  | -44  | %
|Recruiting                    |  |                                 |    |                     | 0   | %                   |                                 |   | 7                   |  | 1   | % |  |   | (7   | ) |  | -100 | %
|Patent expense                |  |                                 | 71  |                     | 10  | %                   |                                 |   | 83                  |  | 8   | % |  |   | (12  | ) |  | -14  | %
|Facilities and related        |  |                                 | 64  |                     | 9   | %                   |                                 |   | 72                  |  | 7   | % |  |   | (8   | ) |  | -11  | %
|Travel                        |  |                                 | 51  |                     | 7   | %                   |                                 |   | 77                  |  | 8   | % |  |   | (26  | ) |  | -34  | %
|Business insurance            |  |                                 | 94  |                     | 13  | %                   |                                 |   | 115                 |  | 11  | % |  |   | (21  | ) |  | -18  | %
|Depreciation                  |  |                                 | 23  |                     | 3   | %                   |                                 |   | 37                  |  | 4   | % |  |   | (14  | ) |  | -38  | %
|Communication and technology  |  |                                 | 32  |                     | 4   | %                   |                                 |   | 33                  |  | 3   | % |  |   | (1   | ) |  | -3   | %
|Office expenses               |  |                                 | 28  |                     | 4   | %                   |                                 |   | 41                  |  | 4   | % |  |   | (13  | ) |  | -32  | %
|Other                         |  |                                 | 68  |                     | 9   | %                   |                                 |   | 21                  |  | 2   | % |  |   | 47   |   |  | 224  | %
|                              |  |                                 |     |                     |     |                     |                                 |   |                     |  |     |   |  |   |      |   |  |      |  
|Total                         |  | $                               | 734 |                     | 100 | %                   |                                 | $ | 1,026               |  | 100 | % |  | $ | (292 | ) |  | -28  | %
|                              |  |                                 |     |                     |     |                     |                                 |   |                     |  |     |   |  |   |      |   |  |      |  

(in thousands)



|                              |  |                               |       |                     |     |                     |                               |   |                     |  |     |   |  |   |        |   |  |      |  
|----------------------------- |  | ----------------------------- | ----- | ------------------- | --- | ------------------- | ----------------------------- | - | ------------------- |  | --- | - |  | - | ------ | - |  | ---- | -
|                              |  | Six
MonthsEndedMarch 31, 2010 |       | % ofExpenseCategory |     |                     | Six
MonthsEndedMarch 31, 2009 |   | % ofExpenseCategory |  |     |   |  |   |        |  
|                              |  |                               |       |                     |     | Increase (Decrease) |                              
|                              |  |                               |       |                     |     | $                   |                               |   | %                   | 
|Professional/outside services |  | $                             | 724   |                     | 49  | %                   |                               | $ | 1,189               |  | 46  | % |  | $ | (465   | ) |  | -39  | %
|Recruiting                    |  |                               |      |                     | 0   | %                   |                               |   | 31                  |  | 1   | % |  |   | (31    | ) |  | -100 | %
|Patent expense                |  |                               | 73    |                     | 5   | %                   |                               |   | 377                 |  | 14  | % |  |   | (304   | ) |  | -81  | %
|Facilities and related        |  |                               | 139   |                     | 9   | %                   |                               |   | 143                 |  | 5   | % |  |   | (4     | ) |  | -3   | %
|Travel                        |  |                               | 100   |                     | 7   | %                   |                               |   | 285                 |  | 11  | % |  |   | (185   | ) |  | -65  | %
|Business insurance            |  |                               | 186   |                     | 13  | %                   |                               |   | 230                 |  | 9   | % |  |   | (44    | ) |  | -19  | %
|Depreciation                  |  |                               | 47    |                     | 3   | %                   |                               |   | 73                  |  | 3   | % |  |   | (26    | ) |  | -36  | %
|Communication and technology  |  |                               | 62    |                     | 4   | %                   |                               |   | 121                 |  | 5   | % |  |   | (59    | ) |  | -49  | %
|Office expenses               |  |                               | 59    |                     | 4   | %                   |                               |   | 104                 |  | 4   | % |  |   | (45    | ) |  | -43  | %
|Other                         |  |                               | 90    |                     | 6   | %                   |                               |   | 58                  |  | 2   | % |  |   | 32     |   |  | 55   | %
|                              |  |                               |       |                     |     |                     |                               |   |                     |  |     |   |  |   |        |   |  |      |  
|Total                         |  | $                             | 1,480 |                     | 100 | %                   |                               | $ | 2,611               |  | 100 | % |  | $ | (1,131 | ) |  | -43  | %
|                              |  |                               |       |                     |     |                     |                               |   |                     |  |     |   |  |   |        |   |  |      |  

Professional/outside services include legal, accounting and other outside services retained by the Company
and its subsidiaries. All periods include normally occurring legal and accounting expenses related to SEC compliance and other corporate matters. Professional/outside services expense was $303,000 during the three months ended March 31, 2010
compared to $540,000 in the comparable prior period. During the six months ended March 31, 2010, professional/outside services expense was $724,000 compared to $1,189,000 in the comparable prior period. The decrease in professional fees
primarily relates to a reduction in expenses at Arrowhead primarily related to lower legal and printing fees and the non-recurrence of a charge at Calando related to a fee



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associated with a financing in the prior period. Also, the Company incurred certain legal fees related to the establishment of subsidiaries which was not repeated in the current quarter. These
reductions were somewhat offset by higher costs related to NASDAQ fees associated with increased shares outstanding.

Patent
expense was $71,000 during the three months ended March 31, 2010 compared to $83,000 in the comparable prior period. During the six months ended March 31, 2010, patent expense was $73,000 compared to $377,000 in the comparable prior
period. Patent expense was comparable in the current quarter; for the six months ended March 31, 2010, patent expense decreased $184,000 at Calando, and patent expense decreased $120,000 at Unidym. Patent expense during the six months ended
March 31, 2009 was primarily related to patent costs at Calando of $221,000 prior to the license agreements to Cerulean, and $156,000 at Unidym for patent costs related to Nanoconduction which were not repeated. The Company expects to continue
to invest in patent protection as the Company extends and maintains protection for its current portfolios and files new patent applications as its product applications are improved. The cost will vary depending on the needs of the Company.

Travel expense was $51,000 during the three months ended March 31, 2010 compared to $77,000 in the comparable prior
period. During the six months ended March 31, 2010, travel expense was $100,000 compared to $285,000 in the comparable prior period. Travel expense includes recurring expenses related to travel by Company personnel to and from Company locations
in Pasadena and Northern California. Travel expense is also incurred as the Company pursues business initiatives and collaborations throughout the world with other companies and for marketing, investor relations, fund raising and public relations
purposes. During the six months ended March 31, 2010, travel expense decreased $185,000, compared to the six months ended March 31, 2009 primarily due to a reduction of travel costs at Unidym of $142,000 due to reduction in employees,
mainly as a result of the closure of its Texas facility. Travel expenses can fluctuate from quarter to quarter and from year to year depending on current projects and activities.

Business insurance expense was $94,000 during the three months ended March 31, 2010 compared to $115,000 in the comparable prior
period. During the six months ended March 31, 2010, business insurance expense was $186,000 compared to $230,000 in the comparable prior period. The decrease is due to generally lower rates in insurance markets and a reduction in coverage for
clinical trials with the termination of the Phase 2 clinical study for IT-101, and the reduction in the number of facilities at Unidym requiring insurance. This expense can fluctuate as a result of changes in the market and the status of clinical
trials.

Communication and technology expense was $32,000 during the three months ended March 31, 2010 compared to
$33,000 in the comparable prior period. During the six months ended March 31, 2010, communication and technology expense was $62,000 compared to $121,000 in the comparable prior period. The decrease in communication and technology cost is due
to lower technology consulting expense at Unidym and generally lower telephone and software maintenance cost at Arrowhead.

Office expense was $28,000 during the three months ended March 31, 2010 compared to $41,000 in the comparable prior period. During
the six months ended March 31, 2010, office expense was $59,000 compared to $104,000 in the comparable prior period. The reduction in office expense is primarily related to the closing of the facilities and the reduction in employees.

Research and Development Expenses  Three and six months ended March 31, 2010 compared to the three and six months ended
March 31, 2009

R&D expenses are primarily related to activities within Arrowheads Subsidiaries. The
following tables provide detail of general and administrative expenses for the three and six months ended March 31, 2010 as compared to the three and six months ended March 31, 2009.



23



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(in thousands)



|                                 |  |                                 |     |   |                     |                     |   |                                 |   |                     |  |     |   |  |   |        |   |  |      |  
|-------------------------------- |  | ------------------------------- | --- | - | ------------------- | ------------------- | - | ------------------------------- | - | ------------------- |  | --- | - |  | - | ------ | - |  | ---- | -
|                                 |  | Three
MonthsEndedMarch 31, 2010 |     |   | % ofExpenseCategory |                     |   | Three
MonthsEndedMarch 31, 2009 |   | % ofExpenseCategory |  |     |   |  |   |        |  
|                                 |  |                                 |     |   |                     | Increase (Decrease) |  
|                                 |  |                                 |     |   |                     | $                   |   |                                 | % |                    
|Outside labs & contract services |  | $                               | 67  |   |                     | 19                  | % |                                 | $ | 837                 |  | 55  | % |  | $ | (770   | ) |  | -92  | %
|License, royalty & milestones    |  |                                 | 74  |   |                     | 21                  | % |                                 |   | 115                 |  | 8   | % |  |   | (41    | ) |  | -36  | %
|Laboratory supplies & services   |  |                                 | (20 | ) |                     | -6                  | % |                                 |   | 65                  |  | 4   | % |  |   | (85    | ) |  | -131 | %
|Facilities and related           |  |                                 | 80  |   |                     | 23                  | % |                                 |   | 315                 |  | 21  | % |  |   | (235   | ) |  | -75  | %
|Sponsored research               |  |                                 | 25  |   |                     | 7                   | % |                                 |   | 9                   |  | 1   | % |  |   | 16     |   |  | 178  | %
|Depreciation - R&D-related       |  |                                 | 70  |   |                     | 20                  | % |                                 |   | 130                 |  | 9   | % |  |   | (60    | ) |  | -46  | %
|Other research expenses          |  |                                 | 55  |   |                     | 16                  | % |                                 |   | 36                  |  | 2   | % |  |   | 19     |   |  | 53   | %
|                                 |  |                                 |     |   |                     |                     |   |                                 |   |                     |  |     |   |  |   |        |   |  |      |  
|Total                            |  | $                               | 351 |   |                     | 100                 | % |                                 | $ | 1,507               |  | 100 | % |  | $ | (1,156 | ) |  | -77  | %
|                                 |  |                                 |     |   |                     |                     |   |                                 |   |                     |  |     |   |  |   |        |   |  |      |  

(in thousands)



|                                 |  |                               |     |   |                     |                     |   |                               |   |                     |  |     |   |  |   |        |   |  |      |  
|-------------------------------- |  | ----------------------------- | --- | - | ------------------- | ------------------- | - | ----------------------------- | - | ------------------- |  | --- | - |  | - | ------ | - |  | ---- | -
|                                 |  | Six
MonthsEndedMarch 31, 2010 |     |   | % ofExpenseCategory |                     |   | Six
MonthsEndedMarch 31, 2009 |   | % ofExpenseCategory |  |     |   |  |   |        |  
|                                 |  |                               |     |   |                     | Increase (Decrease) |  
|                                 |  |                               |     |   |                     | $                   |   |                               | % |                    
|Outside labs & contract services |  | $                             | 116 |   |                     | 19                  | % |                               | $ | 3,481               |  | 64  | % |  | $ | (3,365 | ) |  | -97  | %
|License, royalty & milestones    |  |                               | 77  |   |                     | 12                  | % |                               |   | 355                 |  | 7   | % |  |   | (278   | ) |  | -78  | %
|Laboratory supplies & services   |  |                               | (10 | ) |                     | -2                  | % |                               |   | 251                 |  | 5   | % |  |   | (261   | ) |  | -104 | %
|Facilities and related           |  |                               | 189 |   |                     | 30                  | % |                               |   | 662                 |  | 12  | % |  |   | (473   | ) |  | -71  | %
|Sponsored research               |  |                               | 50  |   |                     | 8                   | % |                               |   | 120                 |  | 2   | % |  |   | (70    | ) |  | -58  | %
|Depreciation - R&D-related       |  |                               | 142 |   |                     | 23                  | % |                               |   | 273                 |  | 5   | % |  |   | (131   | ) |  | -48  | %
|Other research expenses          |  |                               | 65  |   |                     | 10                  | % |                               |   | 253                 |  | 5   | % |  |   | (188   | ) |  | -74  | %
|                                 |  |                               |     |   |                     |                     |   |                               |   |                     |  |     |   |  |   |        |   |  |      |  
|Total                            |  | $                             | 629 |   |                     | 100                 | % |                               | $ | 5,395               |  | 100 | % |  | $ | (4,766 | ) |  | -88  | %
|                                 |  |                               |     |   |                     |                     |   |                               |   |                     |  |     |   |  |   |        |   |  |      |  

Outside lab and services expense was $67,000 during the three months ended March 31, 2010 compared to
$837,000 in the comparable prior period. During the six months ended March 31, 2010, outside lab and services expense was $116,000 compared to $3,481,000 in the comparable prior period. The decrease of $770,000 during the current quarter is
primarily related to a reduction in outside lab services of $717,000 at Calando and a reduction of $53,000 at Unidym. The decrease of $3.4 million during the six months ended March 31, 2010 is primarily related to a reduction in outside lab
services of $2.6 million at Calando and a reduction of $588,000 at Unidym. The reduction at Calando was a result of the advanced state of the IT-101 phase 1 clinical trial, the decision to close the IT-101 phase 2 clinical trials in connection with
the agreement with Cerulean, completion of preparatory work for the CALAA-01 phase 1 clinical trial and the suspension of development efforts for CALAA-02. During fiscal 2009, process development and preclinical expenses for Calandos drug
candidate CALAA-02, together with the clinical trial expenses for CALAA-01 (Phase I) and IT-101 (Phase I and II) totaled approximately $2.9 million. However, the expenses were significantly reduced by June 30, 2009 when the Calando facility was
closed.

Licensing fees, royalty and milestones expense was $74,000 during the three months ended March 31, 2010 compared
to $115,000 in the comparable prior period. During the six months ended March 31, 2010, licensing fees, royalty and milestones expense was $77,000 compared to $355,000 in the comparable prior period. Licensing fees, royalty and milestones
expenses during the six months ended March 31, 2009 consisted primarily of amounts paid by Unidym under the terms of its license agreement with Rice University in the amount of $57,000, and Calandos license fees to Caltech in the amount
of $25,000, as well as an accrual of $200,000 related to the Nanoconduction acquisition, which was a one-time occurrence and not repeated in fiscal 2010.

Laboratory supplies and services expense was ($20,000) during the three months ended March 31, 2010 compared to $65,000 in the
comparable prior period. During the six months ended March 31, 2010, laboratory supplies and services expense was ($10,000) compared to $251,000 in the comparable prior period. Laboratory supplies and services consist primarily of materials,
supplies and services consumed in the laboratory. During the three months ended March 31, 2010, a credit of $35,000 was recorded related to certain aged and cancelled payables related to Nanoconduction; in addition, the decrease is due to the
scale down of the Unidym operations and the closing of Calandos lab.

Facilities expense was $80,000 during the three
months ended March 31, 2010 compared to $315,000 in the comparable prior period. During the six months ended March 31, 2010, facilities expense was $189,000 compared to $662,000 in the comparable prior period. The decrease in facilities
related expenses primarily related to the closure of Unidyms Texas facilities and Menlo Park, California facility.



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Sponsored research expense was $25,000 during the three months ended March 31, 2010
compared to $9,000 in the comparable prior period. During the six months ended March 31, 2010, sponsored research expense was $50,000 compared to $120,000 in the comparable prior period. Sponsored research expense during the quarter related to
Unidyms funding of a project at Duke University. Sponsored research expense decreased during the six months ended March 31, 2010 as compared to the prior year, as projects were completed (University of Florida) or terminated (Caltech). No
new research projects have been added during fiscal 2010. The only sponsored research agreement currently in place is Unidyms agreement with Duke University.

Depreciation expense was $70,000 during the three months ended March 31, 2010 compared to $130,000 in the comparable prior period.
During the six months ended March 31, 2010, depreciation expense was $142,000 compared to $273,000 in the comparable prior period. The decrease in depreciation expense is primarily due to the disposal of laboratory equipment and leasehold
improvements related to closure of Unidyms and Calandos laboratory facilities in fiscal 2009.

The table below
sets forth the approximate amount of Arrowheads cash expenses for research and development projects at each Subsidiary for the periods described below.



|                                                  |  |                                                    |             |                                                  |   |                                                              |  |   |             
|------------------------------------------------- |  | -------------------------------------------------- | ----------- | ------------------------------------------------ | - | ------------------------------------------------------------ |  | - | ------------
|Name of Subsidiary / Project                      |  | Projectexpenses forthree months endedMarch 31,2010 |             | Projectexpenses forsix months endedMarch 31,2010 |   | Projectexpenses frominception
ofProject throughMarch 31,2010
|                                                  |  |                                                    |            
|Calando Pharmaceuticals, Inc. / CALAA-01 & IT 101 |  | $                                                  | 0.1 Million |                                                  | $ | 0.2 Million                                                  |  | $ | 40.4 Million
|                                                  |  |                                                    |            
|Unidym, Inc. / Thin Film Carbon Nanotubes         |  |                                                    | 0.7 Million |                                                  |   | 1.8 Million                                                  |  |   | 27.9 Million
|                                                  |  |                                                    |            
|Tego Biosciences Corp. / Fullerene Anti-oxidants  |  |                                                    | 0.1 Million |                                                  |   | 0.1 Million                                                  |  |   | 1.0 Million 
|                                                  |  |                                                    |            
|Agonn Systems, Inc. / CNT based ultracapacitors   |  |                                                    | 0.0 Million |                                                  |   | 0.0 Million                                                  |  |   | 0.5 Million 
|                                                  |  |                                                    |             |                                                  |   |                                                              |  |   |             
|                                                  |  |                                                    |            
|Total of all listed Subsidiaries                  |  | $                                                  | 0.9 Million |                                                  | $ | 2.1 Million                                                  |  | $ | 69.8 Million
|                                                  |  |                                                    |             |                                                  |   |                                                              |  |   |             

Consulting  Three and six months ended
March 31, 2010 compared to the three and six months ended March 31, 2009

Consulting expense was $78,000
during the three months ended March 31, 2010 compared to $344,000 in the comparable prior period. During the six months ended March 31, 2010, consulting expense was $179,000 compared to $933,000 in the comparable prior period. This
reduction is primarily related to a reduction in consulting fees at Calando. With the closure of the Phase 2 trial for IT-101 and its ultimate licensing to a third party for development, consulting for clinical studies has decreased significantly.

The use of consultants with diverse backgrounds enabled the Company to accomplish various objectives without having to add
full time staff and is expected to continue in fiscal 2010.

Other income (expense)  Three and six months ended
March 31, 2010 compared to the three and six months ended March 31, 2009

Other expense was $14,000 during the
three months ended March 31, 2010 compared to $73,000 in the comparable prior period. During the six months ended March 31, 2010, other expense was $84,000 compared to other income of $567,000 in the comparable prior period. Other
income/expense, net for the three months ended March 31, 2010 was primarily due to $51,000 of expense related to Arrowheads equity in the loss of Nanotope, offset by a $50,000 gain on the disposal of certain lab equipment, as compared to
expense of $73,000 comprised of $60,000 of expense related to Arrowheads equity in the loss of Nanotope, offset by a $52,000 gain on the disposal of equipment, and interest expense of $65,000 during the three months ended March 31, 2009.
During the six months ended March 31, 2010, the change in other income/expense was primarily due to a gain on the sale of equity investment in Ensysce during the quarter ended December 31, 2009.

Leveraged Technology and Revenue Strategy

Arrowhead continues to follow its strategy to leverage technology that is being or has been developed at universities. By doing so,
Arrowhead benefits from work done at those universities and through majority-owned Subsidiaries, which can commercialize the most promising technologies developed from sponsored research and other sources. The Subsidiaries are likely to produce
prototypes to advance their strategies. The Subsidiaries have three primary strategies to generate product sales revenue:



| |  |  | License the products and processes to a third party for a royalty or other payment. By licensing, the Company would not be required to allocate
resources to build a sales or a production infrastructure and could use those resources to develop additional products.
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



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| |  |  | Retain the rights to the products and processes, but contract with a third party for production. The Company would then market the finished products.
This approach would require either the establishment of a sales and distribution network or collaboration with a supplier who has an established sales and distribution network, but would not require investment in production infrastructure.
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | Build production capability in order to produce and market the end products. This last approach would likely require the most capital to build the
production, sales and distribution infrastructure.
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

On a case-by-case basis, the Company and each Subsidiary
will choose the strategy which, in the opinion of management, can be supported by available capital resources and is likely to generate the most favorable return. While the ultimate goal of the Company is to generate revenue through the sale of
products and/or the licensing of technology, the Company does record revenue from grants and from development fees. Revenue from grants and development fees are considered to be reimbursements for efforts performed on behalf of third parties and not
part of the Companys primary strategy to generate revenue.

Contractual Obligations and Commercial Commitments

Unidym incurred various contractual obligations and commercial commitments in connection with the acquisition of Nanoconduction. In
addition, our Subsidiaries incurred contractual obligations and commercial commitments in the normal course of their businesses. They consist of the following:

Capital Lease Obligations

In connection with its acquisition of Nanoconduction, Unidym assumed an equipment lease of $1,677,000, bearing interest at 8% with a
remaining principal balance of $296,419 as of March 31, 2010. The lease requires monthly payments of principal and interest of $75,344 through July 1, 2010. The equipment lease is secured by research and development assets at
Nanoconduction.

Patents and Licenses

Our Subsidiaries have entered into various licensing agreements requiring royalty payments of specified product sales. Some of these
agreements contain provisions for the payment of guaranteed or minimum royalty amounts. Typically, the licensor can terminate our license if we fail to pay minimum annual royalties.

Purchase Commitments

In connection with conducting Phase Ia and Ib trials, in the normal course of business, Calando incurred purchase obligations with vendors
and suppliers for materials and supplies or for manufacture of therapeutic agents, as well as other goods and services. These obligations are generally evidenced by purchase orders that contain the terms and conditions associated with the purchase
arrangements. Calando is committed to accept delivery of such material pursuant to the purchase orders subject to various contract provisions which allow us to delay receipt of such orders or cancel orders beyond certain agreed upon lead times.
Cancellations may result in cancellation costs payable by us.

Off-Balance Sheet Arrangements

We do not have and have not had any off-balance sheet arrangements or relationships.



|ITEM 3. | QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.
|------- | -----------------------------------------------------------

Disclosure not required as a result of the Companys status as a smaller reporting company.



|ITEM 4T. | CONTROLS AND PROCEDURES.
|-------- | ------------------------

Our Chief Executive Officer and our Chief Financial Officer, after evaluating our disclosure controls and procedures (as
defined in Rules 13a-15(e) and 15d-15(e)) of the Securities Exchange Act of 1934, as amended (the Exchange Act) as of the end of the period covered by this Quarterly Report on Form 10-Q (the Evaluation Date), have concluded
that, as of the Evaluation Date, our disclosure controls and procedures are effective to ensure that information we are required to disclose in reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported
within the time periods specified in SEC rules and forms, and to ensure that information required to be disclosed by us in such reports is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial
Officer where appropriate, to allow timely decisions regarding required disclosure.

No change in the Companys internal
controls over financial reporting (as defined in Rule 13a-15(f) under the Exchange Act) occurred during the Companys most recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, our internal control
over financial reporting.



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PART IIOTHER INFORMATION



|ITEM 1. | LEGAL PROCEEDINGS.
|------- | ------------------

From
time to time, we may be involved in routine legal proceedings, as well as demands, claims and threatened litigation, which arise in the normal course of our business. We believe there is no litigation pending that could, individually or in the
aggregate, have a material adverse effect on our results of operations or financial condition.



|ITEM 1A. | RISK FACTORS
|-------- | ------------

We are a
development stage company and we have limited historical operations. We urge you to consider our likelihood of success and prospects in light of the risks, expenses and difficulties frequently encountered by entities at similar stages of
development.

The following is a summary of certain risks we face. They are not the only risks we face. Additional risks of
which we are not presently aware or that we currently believe are immaterial may also harm our business and results of operations. The trading price of our Common Stock could decline due to the occurrence of any of these risks, and investors could
lose all or part of their investment. In assessing these risks, investors should also refer to the other information contained or incorporated by reference in our other filings with the SEC.

Risks Related to Our Financial Condition

We do not have sufficient cash reserves to fund our activities at their current pace beyond this year.

Our plan of operations is to provide substantial amounts of development funding and financial support for our majority-owned subsidiaries over an extended
period of time. Our Board of Directors adopted a cash conservation strategy that scaled back our financial support for our majority-owned subsidiaries, Unidym and Calando. This has influenced Unidyms decision to engage partners for its
capital-intensive bulk CNT manufacturing and concentrate its resources on its CNT inks and CNT-based film products and Calandos decision to curtail internal R&D efforts for its drug delivery platforms and clinical candidates and seek
partners for future development of its drug candidates. Management has developed a plan based upon the latest financing (See Note 6  Stockholders Equity) which includes the December 2009 financing and other transactions. The plan shows
that the Company has enough cash to fund operations through September 30, 2010. Should a shortfall occur in expected cash receipts, the plan has contingencies to reduce costs in order to operate through September 30, 2010 without
additional financing.

We may need to obtain additional capital to support our projects, and we may plan to do so by
out-licensing technology, selling one or more of our subsidiaries, securing funded partnerships, conducting one or more private placements of equity securities of the Company or our subsidiaries, selling additional securities in a registered public
offering, or through a combination of one or more of such financing alternatives. However, there can be no assurance that we will be successful in any of these endeavors or, if we are successful, that such transactions will be accomplished on
favorable terms. If we are unable to obtain additional capital, we will be required to implement additional cash saving measures by limiting further activities at Unidym, or at the Company, which could materially harm our business and our ability to
achieve cash flow in the future, including delaying or reducing implementation of certain aspects of our plan of operations. Even if we are successful in obtaining additional capital, because we and each subsidiary are separate entities, it could be
difficult or impossible to allocate funds in a way that meets the needs of all entities.

A substantial portion of Unidyms
intellectual property is licensed from Rice University and the Rice license includes an insolvency provision.

Through
its merger with Carbon Nanotechnologies, Inc. (CNI), Unidym acquired a license to certain intellectual property from Rice University. Under the license, Unidym must meet a solvency test in order to retain the rights to the licensed
technology. Although Unidym is not insolvent at this time, if Unidym does not obtain additional capital, it is likely that it would become insolvent



27



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and the Rice license would be subject to potential termination. If the Rice license terminates, Unidym would lose exclusivity in the fields of use covered by the Rice license and its business
would be materially and irrevocably harmed. In this case, the likelihood that the Company would realize any return on its investment in Unidym would be substantially diminished, if not eliminated entirely. This would likely materially and
irrevocably harm the value of the Company.

The current financial market conditions may exacerbate certain risks affecting our business.

Neither the Company nor our subsidiaries generate substantial revenue, and, to date, our operations, research and
development activities have been primarily funded through the sale of Company securities and securities of our subsidiaries. Current market conditions are likely to impair our ability to raise the capital we need. If we are unable to secure
additional cash resources from the sale of securities or other sources, it could become necessary to further slow, interrupt or close down development efforts at Unidym. In addition, we may have to make additional cuts in expenses at the Company,
which could impair our ability to manage our business and our subsidiaries. Even if investment capital is available to us, the terms may be onerous in light of the state of the current market. If investment capital is needed and available to Unidym
and/or Calando and the Company does not have the funds to make a pro rata investment, our ownership interest could be significantly diluted. The sale of additional Company stock to fund operations could result in significant dilution to
stockholders.

The strategy for eventual monetization of our subsidiaries will likely depend on our ability to exit our
ownership position in each subsidiary in an orderly manner. Exit opportunities could include an initial public offering (IPO) for the subsidiary or acquisition of the subsidiary by another company. Due to the current economic climate,
companies are adopting conservative acquisition strategies and, even if there is interest, they may not be able to acquire our subsidiaries on terms that are attractive to us, if at all. These factors could reduce the realizable return on our
investment if we are able to sell a subsidiary. Additionally, the market for IPOs is severely limited, which limits public exit opportunities for our subsidiaries.

We may not be able to maintain our listing on the NASDAQ Capital Market.

Our Common Stock trades on the NASDAQ Capital Market, which has certain compliance requirements for continued listing of common stock. We
have in the past been subject to delisting procedures due to a drop in the price of our Common Stock. If our minimum closing bid price per share falls below $1.00 for a period of 30 consecutive trading days in the future, we may again be subject to
delisting procedures. As of the close of business on April 30, 2010, our Common Stock had a closing bid price of $1.53 per share. We must also meet additional continued listing requirements contained in NASDAQ Marketplace Rule 5550(b), which
requires that we have either (1) a minimum of $2,500,000 in stockholders equity, (2) $35,000,000 market value of listed securities held by non-affiliates or (3) $500,000 of net income from continuing operations for the most
recently completed fiscal year (or two of the three most recently completed fiscal years). As of April 30, 2010, based on our closing price as of that day, the market value of our securities held by non-affiliates exceeded $90,000,000 and we
were in compliance with NASDAQ Marketplace Rule 5550(b). There can be no assurance that we will continue to meet the continued listing requirements.

Delisting could reduce the ability of our shareholders to purchase or sell shares as quickly and as easily as they have done
historically. For instance, failure to obtain listing on another market or exchange may make it more difficult for traders to sell our securities. Broker-dealers may be less willing or able to sell or make a market in our Common Stock. Not
maintaining our NASDAQ Capital Market listing may (among other effects):



| |  |  | result in a decrease in the trading price of our Common Stock;
| | - |  | --------------------------------------------------------------



| |  |  | lessen interest by institutions and individuals in investing in our Common Stock;
| | - |  | ---------------------------------------------------------------------------------



| |  |  | make it more difficult to obtain analyst coverage; and
| | - |  | ------------------------------------------------------



| |  |  | make it more difficult for us to raise capital in the future.
| | - |  | -------------------------------------------------------------

We have debt on our consolidated balance sheet, which could have consequences if we were unable to repay the principal or interest due.

Unidym. We have debt on our consolidated balance sheet, including a capital lease obligation acquired in connection
with Unidyms acquisition of Nanoconduction, Inc. As of March 31, 2010, the capital lease obligation requires us to pay a total of $296,419 in four monthly payments of approximately $75,000 each for capital equipment at Unidyms
Sunnyvale, California location and the equipment itself serves as collateral for the debt. Unidyms ability to make payments on its indebtedness will depend on its ability to conserve the cash that it has on hand and to generate cash in the
future. Neither Unidym nor the Company currently generates significant revenue. Because Unidym does not currently have a substantial amount of cash on hand, Unidym might be required to divert cash from development activities or to generate cash via
debt or equity financing to be able to meet the monthly payment requirements under the capital lease obligation. This, to some extent, is subject to general economic, financial, competitive, legislative, regulatory and other factors that are beyond
our control. Also, given the current economic climate, financing options might be limited going forward, which could prevent Unidym from obtaining the necessary funds to pay its indebtedness when due. Because the equipment serves as collateral for
the debt, if Unidym is unable to make the monthly payments when due, the lessor of the equipment, at its discretion, may seize the equipment and Unidym would not be able to use the equipment in its development activities.

Calando. Calando has a $500,000 unsecured convertible promissory note outstanding. The note bears 10% interest accrued annually
and matures in November 2010. The note is also payable at two times face value in certain events, including, among other things, the license of Calandos siRNA delivery system. Following maturity, the note becomes payable on demand. If Calando
is unable to meet its obligations to the bearer of the note after maturity, we may also not be in a position to lend Calando sufficient cash to pay such demand note. Unless other sources of financing become available, this could result in
Calandos insolvency.



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Our subsidiaries have entered into technology license agreements with third parties that require us to
satisfy obligations to keep them effective and, if these agreements are terminated, our technology and our business would be seriously and adversely affected.

Through our subsidiaries, we have entered into exclusive, long-term license agreements with Rice University, California Institute of
Technology, Alnylam Pharmaceuticals, Inc. and other entities to incorporate their proprietary technologies into our proposed products. These license agreements require us to pay royalties and satisfy other conditions, including conditions related to
the commercialization of the licensed technology. We cannot give any assurance that we will successfully incorporate these technologies into marketable products or, if we do, whether sales will be sufficient to recover the amounts that we are
obligated to pay to the licensors. Failure by us to satisfy our obligations under these agreements may result in the modification of the terms of the licenses, such as by rendering them non-exclusive, or may give our licensors the right to terminate
their respective agreement with us, which would limit our ability to implement our current business plan and harm our business and financial condition.

Risks Related to Our Business Model and Company

We are a development stage company and our success is subject to the substantial risks inherent in the establishment of a new business venture.

The implementation of our business strategy is still in the development stage. We currently own majority interests in
two subsidiary companies, investments in two early stage biotech companies and, through Unidym, one university research project at Duke University. Our business and operations should be considered to be in the development stage and subject to all of
the risks inherent in the establishment of a new business venture. Accordingly, our intended business and operations may not prove to be successful in the near future, if at all. Any future success that we might enjoy will depend upon many factors,
several of which may be beyond our control, or which cannot be predicted at this time, and which could have a material adverse effect upon our financial condition, business prospects and operations and the value of an investment in the company.

The costs to fund the operations of Unidym is difficult to predict, and our anticipated expenditures in support of Unidym may increase
or decrease for a variety of reasons.

Development, manufacturing and sale of cost-effective electronic products
incorporating carbon nanotubes may require significant additional investment and take a long time. It is possible that the development and scale up of Unidyms carbon nanotube manufacturing effort and its development and scale up of its
transparent conductive film products could be delayed for a number of reasons, including unforeseen difficulties with the technology development and delays in adoption of the technology by customers. Any delay would result in additional unforeseen
costs, which would harm our results of operations. Due to these uncertainties, we cannot reasonably estimate the size, nature or timing of the costs to complete the development of Unidyms products or net cash inflows from Unidyms current
activities.

Calando may be unable to find additional partners to license its technologies.

As part of our cash conservation strategy that scales back our financial support for Calando at this time, Calando has closed its
laboratory facilities, eliminated its technical employees and has shifted its focus to licensing its technologies to partners. Currently, Calando has one licensing partner, but there can be no assurance that Calando will be able to find additional
partners to license its technologies upon terms favorable to Calando.

If Calando licenses its technologies, it will lose a
considerable amount of control over its intellectual property and may not receive adequate licensing revenues in exchange.

The business model of our subsidiaries has historically been to develop new nanotechnologies and to exploit the intellectual property
created through the research and development process to develop commercially successful products. Calando has licensed a portion of its technology to Cerulean Pharma, Inc. and intends to pursue further licensing arrangements with other
companies. As Calando licenses its technology to other companies, it will lose control over certain of the technologies it licenses and will be unable to significantly direct the commercialization of its technologies. In addition,
Calandos licensees may not be successful in the further commercialization of Calandos technologies and anticipated revenues from such license agreements may be less than expected or may not be paid at all.

There are substantial inherent risks in attempting to commercialize new technological applications, and, as a result, we may not be able to
successfully develop nanotechnology for commercial use.

The Company finances research and development of
nanotechnology, which is a new and unproven field. Our scientists and engineers are working on developing technology in various stages. However, such technologys commercial feasibility and acceptance is unknown. Scientific research and
development requires significant amounts of capital and takes an extremely long time to reach commercial viability, if at all. To date, our research and development projects have not produced commercially viable applications, and may never do so.
During the research and development process, we may experience technological barriers that we may be unable to overcome. For example, our scientists must determine how to design and develop nanotechnology applications for potential products designed
by third parties for use in cost-effective manufacturing processes. Because of these uncertainties, it is possible that none of our potential applications will be successfully developed. If we are unable to successfully develop nanotechnology
applications for commercial use, we will be unable to generate revenue or build a sustainable or profitable business.



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Because we have not generated significant revenues to cover our operating expenses, we are dependent
on raising additional capital from investors or lenders.

To date, we have only generated a small amount of revenue as
a result of our current plan of operations. Given our strategy of financing new and unproven technology research, there is no assurance we would ever generate significant revenues. Our revenue-producing opportunities depend on liquidity events
within our subsidiaries, such as a sale of the subsidiary, licensing transaction or initial public offering. We cannot be certain that we will be able to create a liquidity event for any of our subsidiaries and, even if we are able to, we cannot be
certain of the timing or the potential proceeds to Arrowhead as a stockholder. Accordingly, our revenue prospects are uncertain and we must plan to finance our operations through the sales of equity securities or debt financing. If we are unable to
continue raising operating capital from these sources, we may be forced to curtail or cease our operations.

We will need to achieve
commercial acceptance of our applications to generate revenues and achieve profitability.

Even if our research and development yields
technologically feasible applications, we may not successfully develop commercial products, and even if we do, we may not do so on a timely basis. If our research efforts are successful on the technology side, it could take at least several years
before this technology will be commercially viable. During this period, superior competitive technologies may be introduced or customer needs may change, which will diminish or extinguish the commercial uses for our applications. Because
nanotechnology is an emerging field, the degree to which potential consumers will adopt nanotechnology-enabled products is uncertain. We cannot predict when significant commercial market acceptance for nanotechnology-enabled products will develop,
if at all, and we cannot reliably estimate the projected size of any such potential market. If markets fail to accept nanotechnology-enabled products, we may not be able to generate revenues from the commercial application of our technologies. Our
revenue growth and achievement of profitability will depend substantially on our ability to introduce new technological applications to manufacturers for products accepted by customers. If we are unable to cost-effectively achieve acceptance of our
technology among original equipment manufacturers and customers, or if the associated products do not achieve wide market acceptance, our business will be materially and adversely affected.

We will need to establish additional relationships with strategic and development partners to fully develop and market our products.

We do not possess all of the resources necessary to develop and commercialize products that may result from our
technologies on a mass scale. Unless we expand our product development capacity and enhance our internal marketing, we will need to make appropriate arrangements with strategic partners to develop and commercialize current and future products. If we
do not find appropriate partners, or if our existing arrangements or future agreements are not successful, our ability to develop and commercialize products could be adversely affected. Even if we are able to find collaborative partners, the overall
success of the development and commercialization of product candidates in those programs will depend largely on the efforts of other parties and is beyond our control. In addition, in the event we pursue our commercialization strategy through
collaboration, there are a variety of attendant technical, business and legal risks, including:



| |  |  | a development partner would likely gain access to our proprietary information, potentially enabling the partner to develop products without us or
design around our intellectual property;
| | - |  | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | we may not be able to control the amount and timing of resources that our collaborators may be willing or able to devote to the development or
commercialization of our product candidates or to their marketing and distribution; and
| | - |  | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | disputes may arise between us and our collaborators that result in the delay or termination of the research, development or commercialization of our
product candidates or that result in costly litigation or arbitration that diverts our managements resources.
| | - |  | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

The
occurrence of any of the above risks could impair our ability to generate revenues and harm our business and financial condition.

We
need to retain a controlling interest, by ownership, contract or otherwise, in Unidym and Calando in order to avoid potentially being deemed an investment company under the Investment Company Act of 1940.

Companies that have more than 100 U.S. stockholders or are publicly traded in the U.S. or are, or hold themselves out as being, engaged
primarily in the business of investing, reinvesting or trading in securities are subject to regulation under the Investment Company Act of 1940. Unless a substantial part of our assets consists of, and a substantial part of our income is derived
from, interests in majority-owned subsidiaries and companies that we primarily control, whether by contract or otherwise, we may be required to register and become subject to regulation under the Investment Company Act. Because Investment Company
Act regulation is, for the most part, inconsistent with our strategy of actively managing and operating our portfolio companies, a requirement to operate our business as a registered investment company would restrict our operations and require
additional resources for compliance.



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If we are deemed to be, and are required to register as, an investment company, we will be
forced to comply with substantive requirements under the Investment Company Act, including:



| |  |  | limitations on our ability to borrow;
| | - |  | -------------------------------------



| |  |  | limitations on our capital structure;
| | - |  | -------------------------------------



| |  |  | restrictions on acquisitions of interests in associated companies;
| | - |  | ------------------------------------------------------------------



| |  |  | prohibitions on transactions with our affiliates;
| | - |  | -------------------------------------------------



| |  |  | restrictions on specific investments; and
| | - |  | -----------------------------------------



| |  |  | compliance with reporting, record keeping, voting, proxy disclosure and other rules and regulations.
| | - |  | ----------------------------------------------------------------------------------------------------

In order to avoid regulation under the Investment Company Act, we may choose to make additional pro rata investments in Unidym and
Calando to maintain a controlling interest.

Nanotechnology-enabled products are new and may be viewed as being harmful to human health
or the environment.

There is public concern regarding the human health, environmental and ethical implications of nanotechnology that
could impede market acceptance of products developed through these means. Nanotechnology-enabled products could be composed of materials such as carbon, silicon, silicon carbide, germanium, gallium arsenide, gallium nitride, cadmium selenide or
indium phosphide, which may prove to be unsafe or harmful to human health or to the environment because of the size, shape or composition of the nanostructures. For this reason, these nanostructures may prove to present risks to human health or the
environment that are different from and greater than the better understood risks that may be presented by the constituent materials in non-nanoscale forms. Because of the potential, but at this point unknown, risks associated with certain
nanomaterials, government authorities in the U.S. or individual states, and foreign government authorities could, for social or other purposes, prohibit or regulate the use of some or all nanotechnologies. The U.S. Environmental Protection Agency
has in that regard recently taken steps towards regulation of the manufacture and use of certain nanotechnology-enabled materials, including those containing carbon nanotubes or nanosilver. Further, the U.S. National Academy of Sciences/National
Research Council concluded that the U.S. government needs to develop a more robust and coordinated plan for addressing the potential environmental, health, and safety risks of nanomaterials. The regulation and limitation of the kinds of materials
used in or used to develop nanotechnology-enabled products, or the regulation of the products themselves, could halt or delay the commercialization of nanotechnology-enabled products or substantially increase the cost, which will impair our ability
to achieve revenue from the license of nanotechnology applications.

We may not be able to effectively secure first-tier research and
development projects when competing against other ventures.

We compete with a substantial number of other companies
that fund early-stage, scientific research at universities to secure rights to promising technologies. In addition, many venture capital firms and other institutional investors invest in companies seeking to commercialize various types of emerging
technologies. Many of these companies have greater resources than we do. Therefore, we may not be able to secure the opportunity to finance first-tier research and commercialization projects. Furthermore, should any commercial undertaking by us
prove to be successful, there can be no assurance competitors with greater financial resources will not offer competitive products and/or technologies.

We rely on outside sources for various components and processes for our products.

We rely on third parties for various components and processes for our products. While we try to have at least two sources for each
component and process, we may not be able to achieve multiple sourcing because there may be no acceptable second source, other companies may choose not to work with us, or the component or process sought may be so new that a second source does not
exist, or does not exist on acceptable terms. In addition, due to the recent tightening of global credit and the disruption in the financial markets, there may be a disruption or delay in the performance of our third-party contractors, suppliers or
collaborators. If such third parties are unable to satisfy their commitments to us, our business would be adversely affected. Therefore, it is possible that our business plans will have to be slowed down or stopped completely at times due to our
inability to obtain required raw materials, components and outsourced processes at an acceptable cost, if at all, or to get a timely response from vendors.

We must overcome the many obstacles associated with integrating and operating varying business ventures to succeed.

Our model to integrate and oversee the strategic direction of various subsidiaries and research and development projects presents many
risks, including:



| |  |  | the difficulty of integrating operations and personnel; and
| | - |  | -----------------------------------------------------------



| |  |  | the diversion of our managements attention as a result of evaluating, negotiating and integrating acquisitions or new business ventures.
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------



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If we are unable to timely and efficiently design and integrate administrative and
operational support for our subsidiaries, we may be unable to manage projects effectively, which could adversely affect our ability to meet our business objectives and the value of an investment in the Company could decline.

In addition, consummating acquisitions and taking advantage of strategic relationships could adversely impact our cash position, and
dilute stockholder interests, for many reasons, including:



| |  |  | changes to our income to reflect the amortization of acquired intangible assets, including goodwill;
| | - |  | ----------------------------------------------------------------------------------------------------



| |  |  | interest costs and debt service requirements for any debt incurred to fund our growth strategy; and
| | - |  | ---------------------------------------------------------------------------------------------------



| |  |  | any issuance of securities to fund our operations or growth, which dilutes or lessens the rights of current stockholders.
| | - |  | -------------------------------------------------------------------------------------------------------------------------

Our success depends on the attraction and retention of senior management and scientists with relevant expertise.

Our future success will depend to a significant extent on the continued services of our key employees. In addition, we rely on several key
executives to manage each of our subsidiaries. We do not maintain key man life insurance for any of our executives. Our ability to execute our strategy also will depend on our ability to continue to attract and retain qualified scientists, sales,
marketing and additional managerial personnel. If we are unable to find, hire and retain qualified individuals, we could have difficulty implementing our business plan in a timely manner, or at all. Given the Companys current financial
constraints, we may need to terminate additional employees, including senior management and technical employees, or such employees may seek other employment. With these and past reductions, it is possible that valuable know-how will be lost and that
development efforts could be negatively affected.

Members of our senior management team and Board may have a conflict of interest in
also serving as officers and/or directors of our subsidiaries.

While we expect that our officers and directors who
also serve as officers and/or directors of our subsidiaries will comply with their fiduciary duties owed to our stockholders, they may have conflicting fiduciary obligations to our stockholders and the minority stockholders of our subsidiaries.
Specifically, Dr. Anzalone, our CEO and President, is the founder, CEO and a board member of each of Nanotope, a regenerative medicine company that is separately financed in which the Company owns a 23% interest, and Leonardo, a drug delivery
company in which the Company owns a 6% interest. Dr. Anzalone owns a noncontrolling interest in the stock of each of Nanotope and Leonardo. To the extent that any of our directors choose to recuse themselves from particular Board actions to
avoid a conflict of interest, the other members of our Board of Directors will have a greater influence on such decisions.

Our efforts
pertaining to the pharmaceutical industry are subject to additional risks.

Our subsidiary, Calando, as well as
minority investments Nanotope and Leonardo, are focused on technology related to new and improved pharmaceutical candidates. Drug development is time consuming, expensive and risky. Even product candidates that appear promising in the early phases
of development, such as in early animal and human clinical trials, often fail to reach the market for a number of reasons, such as:



| |  |  | clinical trial results are not acceptable, even though preclinical trial results were promising;
| | - |  | ------------------------------------------------------------------------------------------------



| |  |  | inefficacy and/or harmful side effects in humans or animals;
| | - |  | ------------------------------------------------------------



| |  |  | the necessary regulatory bodies, such as the U.S. Food and Drug Administration, did not approve our potential product for the intended use; and
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | manufacturing and distribution is uneconomical.
| | - |  | -----------------------------------------------

Clinical trial results are frequently susceptible to varying interpretations by scientists, medical personnel, regulatory personnel,
statisticians and others, which often delays, limits, or prevents further clinical development or regulatory approvals of potential products. If the subsidiaries technology is not cost effective or if the associated drug products do not
achieve wide market acceptance, the value of a subsidiary would be materially and adversely affected.

Any drugs developed by our
subsidiaries may become subject to unfavorable pricing regulations, third-party reimbursement practices or healthcare reform initiatives, thereby harming our business.

Increasing expenditures for healthcare have been the subject of considerable public attention in the U.S. Both private and government
entities are seeking ways to reduce or contain healthcare costs. Numerous proposals that would affect changes in the U.S. healthcare system have been introduced or proposed in Congress and in some state legislatures, including reductions in the cost
of prescription products and changes in the levels at which consumers and healthcare providers are reimbursed for purchases of pharmaceutical products.



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The ability of Calando and our minority investments, Nanotope and Leonardo, to market
products successfully (either on their own or in partnership with other companies) will depend in part on the extent to which third-party payers are willing to reimburse patients for the costs of their products and related treatments. These
third-party payers include government authorities, private health insurers and other organizations, such as health maintenance organizations. Third party payers are increasingly challenging the prices charged for medical products and services. In
addition, the trend toward managed healthcare and government insurance programs could result in lower prices and reduced demand for the products of these companies. Cost containment measures instituted by healthcare providers and any general
healthcare reform could affect their ability to sell products and may have a material adverse effect on them, thereby diminishing the value of the Companys interest in these subsidiaries or any anticipated milestone or royalty payments. We
cannot predict the effect of future legislation or regulation concerning the healthcare industry and third party coverage and reimbursement on our business.

There may be a difference in the investment valuations that we used when making initial and subsequent investments in our subsidiaries and minority
investments and actual market values.

Our investments in our subsidiaries and noncontrolling interests were the result
of negotiation with subsidiary management and equity holders, and the investment valuations were not independently verified. Traditional methods used by independent valuation analysts include a discounted cash flow analysis and a comparable company
analysis. We have not generated a positive cash flow to date and do not expect to generate significant cash flow in the near future. Additionally, we believe that there exist few comparable public companies to provide a meaningful valuation
comparison. Accordingly, we have not sought independent valuation analysis in connection with our investments and may have invested in our various holdings at higher or lower valuations than an independent source would have recommended. There may be
no correlation between the investment valuations that we used over the years for our investments and the actual market values. If we should eventually sell all or a part of any of our consolidated business or that of a subsidiary, the ultimate sale
price may be for a value substantially different than previously determined by us, which could materially and adversely impair the value of our Common Stock.

Risks Related to Our Intellectual Property

If Unidym is unable to raise additional cash or pay its debts, Unidym may lose rights to critical intellectual property.

Unidym is required to meet certain financial covenants pursuant to the Rice University license agreement acquired by Unidym upon its
acquisition of CNI. The Rice license includes financial covenants tested quarterly for compliance. If Unidym fails to meet the financial covenants, the Rice license automatically terminates. If this should happen, the value of Unidyms
intellectual property portfolio would be significantly and adversely affected and Unidym would likely lose patent protection for its products and licensing opportunities for the majority of its CNT intellectual portfolio.

Our ability to protect our patents and other proprietary rights is uncertain, exposing us to the possible loss of competitive advantage.

Our subsidiaries have licensed rights to pending patents and have filed and will continue to file patent applications. The
researchers sponsored by us may also file patent applications that we choose to license. If a particular patent is not granted, the value of the invention described in the patent would be diminished. Further, even if these patents are granted, they
may be difficult to enforce. Even if successful, efforts to enforce our patent rights could be expensive, distracting for management, cause our patents to be invalidated, and frustrate commercialization of products. Additionally, even if patents are
issued and are enforceable, others may independently develop similar, superior or parallel technologies to any technology developed by us, or our technology may prove to infringe upon patents or rights owned by others. Thus, the patents held by or
licensed to us may not afford us any meaningful competitive advantage. If we are unable to derive value from our licensed or owned intellectual property, the value of your investment may decline.

Our ability to develop and commercialize products will depend on our ability to enforce our intellectual property rights and operate without
infringing the proprietary rights of third parties.

Our ability and the ability of our subsidiaries to develop and
commercialize products based on their respective patent portfolios, will depend, in part, on our ability and the ability of our subsidiaries to enforce those patents and operate without infringing the proprietary rights of third parties. There can
be no assurance that any patents that may issue from patent applications owned or licensed by us or any of our subsidiaries will provide sufficient protection to conduct our respective businesses as presently conducted or as proposed to be
conducted, or that we or our subsidiaries will remain free from infringement claims by third parties.

We may be subject to patent
infringement claims, which could result in substantial costs and liability and prevent us from commercializing our potential products.

Because the nanotechnology intellectual property landscape is rapidly evolving and interdisciplinary, it is difficult to conclusively
assess our freedom to operate without infringing on third party rights. However, we are currently aware of certain patent rights held by third parties that, if found to be valid and enforceable, could be alleged to render one or more of our business
lines infringing. If a claim should be brought and is successful, we may be required to pay substantial damages, be forced to abandon any



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affected business lines and/or seek a license from the patent holder. In addition, any patent infringement claims brought against us or our subsidiaries, whether or not successful, may cause us
to incur significant expenses and divert the attention of our management and key personnel from other business concerns. These could negatively affect our results of operations and prospects. There can also be no assurance that patents owned or
licensed by us or our subsidiaries will not be challenged by others.

In addition, if our potential products infringe the
intellectual property rights of third parties, these third parties may assert infringement claims against our customers, and we may be required to indemnify our customers for any damages they suffer as a result of these claims. The claims may
require us to initiate or defend protracted and costly litigation on behalf of customers, regardless of the merits of these claims. If any of these claims succeed, we may be forced to pay damages on behalf of our customers or may be required to
obtain licenses for the products they use. If we cannot obtain all necessary licenses on commercially reasonable terms, we may be unable to continue selling such products.

The technology licensed by our subsidiaries from various third parties may be subject to government rights and retained rights of the originating
research institutions.

We license technology from Caltech, Rice University, and other universities and companies. Our
licensors may have obligations to government agencies or universities. Under their agreements, a government agency or university may obtain certain rights over the technology that we have developed and licensed, including the right to require that a
compulsory license be granted to one or more third parties selected by the government agency.

In addition, our collaborators
often retain certain rights under their agreements with us, including the right to use the underlying technology for noncommercial academic and research use, to publish general scientific findings from research related to the technology, and to make
customary scientific and scholarly disclosures of information relating to the technology. It is difficult to monitor whether our collaborators limit their use of the technology to these uses, and we could incur substantial expenses to enforce our
rights to our licensed technology in the event of misuse.

Risks Related to Regulation of Our Products

Our corporate compliance program cannot guarantee that we are in compliance with all applicable federal and state regulations.

Our operations, including our research and development and our commercialization efforts, such as clinical trials, manufacturing and distribution, are
subject to extensive federal and state regulation. While we have developed and instituted a corporate compliance program, we cannot assure you that the Company or our employees are or will be in compliance with all potentially applicable federal and
state regulations or laws. If we fail to comply with any of these regulations or laws, a range of actions could result, including, but not limited to, the termination of clinical trials, the failure to approve a commercialized product, significant
fines, sanctions, or litigation, any of which could harm our business and financial condition.

If export controls affecting our
products are expanded, our business will be adversely affected.

The federal government regulates the sale and shipment
of numerous technologies by U.S. companies to foreign countries. Our subsidiaries may develop products that might be useful for military and antiterrorism activities. Accordingly, federal government export regulations could restrict sales of these
products in other countries. If the federal government places burdensome export controls on our technology or products, our business would be materially and adversely affected. If the federal government determines that we have not complied with the
applicable export regulations, we may face penalties in the form of fines or other punishment.

Risks Related to our Stock

Stockholder equity interest may be substantially diluted in any additional financing.

Our certificate of incorporation authorizes the issuance of 145,000,000 shares of Common Stock and 5,000,000 shares of Preferred Stock, on
such terms and at such prices as our Board of Directors may determine. As of March 31, 2010, 63,833,753 shares of Common Stock and no shares of Preferred Stock were issued and outstanding. As of March 31, 2010, 1,532,000 shares and
5,003,838 shares were reserved for issuance upon exercise of options granted under our 2000 Stock Option Plan and 2004 Equity Incentive Plan, respectively. As of March 31, 2010, there were warrants outstanding to purchase 19,577,257 shares of
Common Stock. All of the warrants are callable by us under certain market conditions. The issuance of additional securities in financing transactions by us or through the exercise of options or warrants will dilute the equity interests of our
existing stockholders, perhaps substantially, and might result in dilution in the tangible net book value of a share of our Common Stock, depending upon the price and other terms on which the additional shares are issued.



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Our Common Stock price has fluctuated significantly over the last several years and may continue to do
so in the future, without regard to our results of operations and prospects.

Because we are a development stage
company, there are few objective metrics by which our progress may be measured. Consequently, we expect that the market price of our Common Stock will likely continue to fluctuate significantly. We do not expect to generate substantial revenue from
the license or sale of our nanotechnology for several years, if at all. In the absence of product revenue as a measure of our operating performance, we anticipate that investors and market analysts will assess our performance by considering factors
such as:



| |  |  | announcements of developments related to our business;
| | - |  | ------------------------------------------------------



| |  |  | developments in our strategic relationships with scientists within the nanotechnology field;
| | - |  | --------------------------------------------------------------------------------------------



| |  |  | our ability to enter into or extend investigation phase, development phase, commercialization phase and other agreements with new and/or existing
partners;
| | - |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------



| |  |  | announcements regarding the status of any or all of our collaborations or products;
| | - |  | -----------------------------------------------------------------------------------



| |  |  | market perception and/or investor sentiment regarding nanotechnology as the next technological wave;
| | - |  | ----------------------------------------------------------------------------------------------------



| |  |  | announcements regarding developments in the nanotechnology field in general;
| | - |  | ----------------------------------------------------------------------------



| |  |  | the issuance of competitive patents or disallowance or loss of our patent rights; and
| | - |  | -------------------------------------------------------------------------------------



| |  |  | quarterly variations in our operating results.
| | - |  | ----------------------------------------------

We will not have control over many of these factors but expect that they may influence our stock price. As a result, our stock price may
be volatile and any extreme fluctuations in the market price of our Common Stock could result in the loss of all or part of your investment.

The market for purchases and sales of our Common Stock may be very limited, and the sale of a limited number of shares could cause the price to
fall sharply.

Although our Common Stock is listed for trading on the NASDAQ Capital Market, our securities
historically were relatively thinly traded. Our current solvency concerns could serve to exacerbate the thin trading of our securities. For example, mandatory sales of our Common Stock by institutional holders could be triggered if an investment in
our Common Stock no longer satisfies their investment standards and guidelines as a result of the solvency concerns. Accordingly, it may be difficult to sell shares of Common Stock quickly without significantly depressing the value of the stock.
Unless we are successful in developing continued investor interest in our stock, sales of our stock could continue to result in major fluctuations in the price of the stock.

If securities or industry analysts do not publish research reports about our business or if they make adverse recommendations regarding an
investment in our stock, our stock price and trading volume may decline.

The trading market for our Common Stock will
be influenced by the research and reports that industry or securities analysts publish about our business. We do not currently have and may never obtain research coverage by industry or securities analysts. Investors have many investment
opportunities and may limit their investments to companies that receive coverage from analysts. If no industry or securities analysts commence coverage of the Company, the trading price of our stock could be negatively impacted. In the event we
obtain industry or security analyst coverage, if one or more of the analysts downgrade our stock or comment negatively on our prospects, our stock price would likely decline. If one or more of these analysts cease to cover our industry or us or
fails to publish reports about the Company regularly, our Common Stock could lose visibility in the financial markets, which could also cause our stock price or trading volume to decline.

The market price of our Common Stock may be adversely affected by the sale of shares by our management or founding stockholders.

Sales of our Common Stock by our officers, directors and founding stockholders could adversely and unpredictably
affect the price of those securities. Additionally, the price of our Common Stock could be affected even by the potential for sales by these persons. We cannot predict the effect that any future sales of our Common Stock, or the potential for those
sales, will have on our share price. Furthermore, due to relatively low trading volume of our stock, should one or more large stockholders seek to sell a significant portion of its stock in a short period of time, the price of our stock may decline.

We may be the target of securities class action litigation due to future stock price volatility.

In the past, when the market price of a stock has been volatile, holders of that stock have often initiated securities class action
litigation against the company that issued the stock. If any of our stockholders brought a lawsuit against us, we could incur substantial costs defending the lawsuit. The lawsuit could also divert the time and attention of our management.



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We do not intend to declare cash dividends on our Common Stock.

We will not distribute cash to our stockholders unless and until we can develop sufficient funds from operations to meet our ongoing needs
and implement our business plan. The time frame for that is inherently unpredictable, and you should not plan on it occurring in the near future, if at all.

Our Board of Directors has the authority to issue shares of blank check preferred stock, which may make an acquisition of the Company
by another company more difficult.

We have adopted and may in the future adopt certain measures that may have the
effect of delaying, deferring or preventing a takeover or other change in control of the Company that a holder of our Common Stock might consider in its best interest. Specifically, our Board of Directors, without further action by our stockholders,
currently has the authority to issue up to 5,000,000 shares of preferred stock and to fix the rights (including voting rights), preferences and privileges of these shares (blank check preferred). Such preferred stock may have rights,
including economic rights, senior to our Common Stock.



|ITEM 2. | UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS.
|------- | ------------------------------------------------------------

All information under this Item has been previously reported on our Current Reports on Form 8-K.



|ITEM 3. | DEFAULTS UPON SENIOR SECURITIES.
|------- | --------------------------------

None.



|ITEM 4. | (REMOVED AND RESERVED)
|------- | ----------------------



|ITEM 5. | OTHER INFORMATION.
|------- | ------------------

None.



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|ITEM 6. | EXHIBITS.
|------- | ---------



|              |  |                                                                                                                                                                                  
|------------- |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|ExhibitNumber |  | Document Description                                                                                                                                                             
|              | 
|3.1           |  | Amendment No. 1 to the Bylaws of Arrowhead Research Corporation (1)                                                                                                              
|              | 
|31.1          |  | Certification of Chief Executive Officer pursuant to Rule 13a-14(a) of the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002*
|              | 
|31.2          |  | Certification of Chief Financial Officer pursuant to Rule 13a-14(a) of the Securities Exchange Act of 1934, as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002*
|              | 
|32.1          |  | Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002*                               
|              | 
|32.2          |  | Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002*                               



|* | Filed herewith
|- | --------------

|(1) | Incorporated by reference from the current report on Form 8-K, filed by the registrant on April 27, 2010.
|--- | ---------------------------------------------------------------------------------------------------------



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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Issuer has caused this Quarterly
Report on Form 10-Q to be signed on its behalf by the undersigned, thereunto duly authorized.

Dated: May 13, 2010



ARROWHEAD RESEARCH CORPORATIONBy:

/s/    KENNETH A. MYSZKOWSKIKenneth A. MyszkowskiChief Financial Officer




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